Phonological history of English explained

See also: Phonological history of English vowels and Phonological history of English consonants. pronounced as /notice/Like many other languages, English has wide variation in pronunciation, both historically and from dialect to dialect. In general, however, the regional dialects of English share a largely similar (but not identical) phonological system. Among other things, most dialects have vowel reduction in unstressed syllables and a complex set of phonological features that distinguish fortis and lenis consonants (stops, affricates, and fricatives).

This article describes the development of the phonology of English over time, starting from its roots in proto-Germanic to diverse changes in different dialects of modern English.

Abbreviations

In the following description, abbreviations are used as follows:

• C = any consonant
• V = any vowel
• # = end of word
• * = reconstructed
• ** = non-existent
• > = changes into
• >! = changes into, unexpectedly
• < = is derived from
• PreOE = Pre-Old English
• OE = Old English
• EME = Early Middle English
• LME = Late Middle English
• ME = Middle English
• EModE = Early Modern English
• ModE = Modern English
• GA = General American
• RP = Received Pronunciation
• PrePG = Pre-Proto-Germanic
• PG or PGmc = Proto-Germanic
• NWG = Northwest Germanic
• WG = West Germanic
• OHG = Old High German
• MHG = Middle High German
• ModG = Modern German
• PIE = Proto-Indo-European
• Goth = Gothic
• PN = Proto-Norse
• ON = Old Norse
• OEN = Old East Norse
• OWN = Old West Norse
• OS = Old Saxon

Changes by time period from Late Proto-Germanic to Old English

This section summarizes the changes occurring within distinct time periods, covering the last 2,000 years or so. Within each subsection, changes are in approximate chronological order.

The time periods for some of the early stages are quite short due to the extensive population movements occurring during the Migration Period (early AD), which resulted in rapid dialect fragmentation.

Late Proto-Germanic period

This period includes changes in late Proto-Germanic, up to about the 1st century. Only a general overview of the more important changes is given here; for a full list, see the Proto-Germanic article.

• Unstressed word-final pronounced as //a//, pronounced as //e// and pronounced as //o// were lost. Early Germanic languages: barta > late PGmc Germanic languages: bart "you carried (sg)".
• Word-final pronounced as //m// became pronounced as //n//.
  • Word-final pronounced as //n// was then lost after unstressed syllables with nasalization of the preceding vowel. Hence * > early PGmc Germanic languages: dagam > late PGmc Germanic languages: dagą > Old English English, Old (ca.450-1100);: dæġ "day (acc. sg.)". The nasalisation was retained at least into the earliest history of Old English.
• Word-final pronounced as //t// was lost after an unstressed syllable. This followed the loss of word-final pronounced as //n//, because it remained before pronounced as //t//: PrePGmc * > early PGmc Germanic languages: burunt > late PGmc Germanic languages: burun "they carried".
• pronounced as //e// was raised to pronounced as //i// in unstressed syllables.
  • The original vowel remained when followed by pronounced as //r//, and was later lowered to pronounced as //ɑ//.
• Early i-mutation: pronounced as //e// was raised to pronounced as //i// when an pronounced as //i// or pronounced as //j// followed in the next syllable.
  • This occurred before deletion of word-final pronounced as //i//; hence * > early PGmc Germanic languages: uberi > late PGmc Germanic languages: ubiri > German German: über "over". Compare PIE * > early PGmc Germanic languages: uber > late PGmc Germanic languages: ubar > German German: ober "over".
  • But it occurred after the raising of unstressed pronounced as //e// to pronounced as //i//: PIE * > PGmc Germanic languages: berid > Germanic languages: birid "you carry (pl)".
  • This also affected the diphthong pronounced as //eu//, which became pronounced as //iu//.
  • As a consequence of this change, pronounced as //ei// > pronounced as //iː//. The Elder Futhark of the Proto-Norse language still contained different symbols for the two sounds.
• z-umlaut: pronounced as //e// is raised to pronounced as //i// before pronounced as //z//.
  • Early PGmc Germanic languages: mez "me, dative" > late PGmc Germanic languages: miz > Old High German mir, Old Saxon mi, Old Norse mér (with general lowering and lengthening of i before r).
  • This change was only sporadic at best because there were barely any words in which it could have occurred at all, since pronounced as //e// remained only in stressed syllables. The umlauting effect of pronounced as //z// remained, however, and in Old West Norse it was extended to other vowels as well. Hence OEN glaʀ, hrauʀ, OWN gler, hreyrr.
• Pre-nasal raising: pronounced as //e// > pronounced as //i// before nasal + consonant. Pre-PGmc * > PGmc Germanic languages: bendaną > Germanic languages: bindaną > OE bindan > ModE bind (Latin Latin: of-fendō).
  • This was later extended in Pre-Old English times to vowels before all nasals; hence Old English niman "take" but Old High German neman.
• Loss of pronounced as //n// before pronounced as //x//, with nasalization and compensatory lengthening of the preceding vowel.
  • The nasalization was eventually lost, but remained through the Ingvaeonic period.
  • Hence Pre-PGmc * > PGmc Germanic languages: þankijaną > OE þencan > ModE think, but PrePG * > PGmc Germanic languages: þanhtaz > Germanic languages: þą̄htaz > OE English, Old (ca.450-1100);: þōht > ModE thought.
  • This change followed the raising of pronounced as //e// before a nasal: PGmc Germanic languages: þenhaną > Germanic languages: þinhaną > Germanic languages: þį̄haną > Gothic Gothic: þeihan.
• Final-syllable short vowels were generally deleted in words of three syllables or more. PGmc Germanic languages: biridi > Goth Gothic: baíriþ pronounced as //beriθ// "(he) carries" (see above), and also PGmc Germanic languages: -maz, Germanic languages: -miz > Germanic languages: -mz (dative and instrumental plural ending of nouns, 1st person plural ending of verbs, as on the Stentoften Runestone).

Northwest Germanic period

This was the period after the East Germanic languages had split off. Changes during this time were shared with the North Germanic dialects, i.e. Proto-Norse. Many of the changes that occurred were areal, and took time to propagate throughout a dialect continuum that was already diversifying. Thus, the ordering of the changes is sometimes ambiguous, and can differ between dialects.

• Allophonic i-mutation/Germanic umlaut: Short back vowels were fronted when followed in the next syllable by pronounced as //i// or pronounced as //j//, by i-mutation: pronounced as //ɑ// > pronounced as /[æ]/, pronounced as //o// > pronounced as /[ø]/, pronounced as //u// > pronounced as /[y]/
  • In this initial stage, the mutated vowels were still allophonically conditioned, and were not yet distinct as phonemes. Only later, when the pronounced as //i// and pronounced as //j// were modified or lost, were the new sounds phonemicized.
  • i-mutation affected all the Germanic languages except for Gothic, although with a great deal of variation. It appears to have occurred earliest, and to be most pronounced, in the Schleswig-Holstein area (the home of the Anglo-Saxons), and from there to have spread north and south. However, it is possible that this change already occurred in Proto-Germanic proper, in which case the phenomenon would have remained merely allophonic for quite some time. If that is the case, that would be the stage reflected in Gothic, where there is no orthographic evidence of i-mutation at all.
  • Long vowels and diphthongs were affected only later, probably analogically, and not in all areas. Notably, they were not mutated in most (western) Dutch dialects, whereas short vowels were.
• a-mutation: pronounced as //u// is lowered to pronounced as //o// when a non-high vowel follows in the next syllable.
  • This is blocked when followed by a nasal followed by a consonant, or by a cluster with pronounced as //j// in it. Hence PG Germanic languages: gulþą > OE/ModE gold, but PG Germanic languages: guldijaną > OE gyldan > ModE gild.
  • This produces a new phoneme pronounced as //o//, due to inconsistent application and later loss of word-final vowels.
• Final-syllable long vowels were shortened.
  • Final pronounced as //ɔː// becomes pronounced as //o//, later raised to pronounced as //u//. PG Germanic languages: sagō ("saw (tool)") > OE sagu, ON sǫg.
  • Final pronounced as //ɛː// becomes pronounced as //e// in ON (later raised to pronounced as //i//), pronounced as //ɑ// in West Germanic. PG Germanic languages: hailidē ("he/she/it healed") > ON heilði, but OE hǣlde, OHG heilta.
  • The final long diphthong pronounced as //ɔːi// loses its final element and usually develops the same as pronounced as //ɔː// from that point on. PG Germanic languages: gebōi ("gift", dative singular) > NWG Germanic languages: gebō > ON gjǫf, OHG gebu, OE giefe (an apparent irregular development).
• "Overlong" vowels were shortened to regular long vowels.
• PG pronounced as //ɛː// (maybe already pronounced as //æː// by late PG) becomes pronounced as //ɑː//. This preceded final shortening in West Germanic, but postdated it in North Germanic.
• Unstressed diphthongs were monophthongized. pronounced as //ɑi// > pronounced as //eː//, pronounced as //ɑu// > pronounced as //oː//. The latter merged with ō from shortened overlong ô. PG Germanic languages: sunauz ("son", genitive singular) > NWG Germanic languages: sunōz > ON sonar, OE suna, OHG suno; PG Germanic languages: nemai ("he/she/it take", subjunctive) > NWG Germanic languages: nemē > ON nemi, OE nime, OHG neme; PG Germanic languages: stainai ("stone", dative singular) > NWG Germanic languages: stainē > ON steini, OE English, Old (ca.450-1100);: stāne, OHG steine.

West Germanic period

This period occurred around the 2nd to 4th centuries. It is unclear if there was ever a distinct "Proto-West Germanic", as most changes in this period were areal, and likely spread throughout a dialect continuum that was already diversifying further. Thus, this "period" may not have been a real timespan, but may simply cover certain areal changes that did not reach into North Germanic. This period ends with the further diversification of West Germanic into several groups before and during the Migration Period: Ingvaeonic, Istvaeonic (Old Frankish) and Irminonic (Upper German).

• Loss of word-final pronounced as //z//.
  • This change occurred before rhotacization, as original word-final pronounced as //r// was not lost.
  • But it must have occurred after the Northwest Germanic split, since word-final pronounced as //z// was not eliminated in Old Norse, instead merging with pronounced as //r//.
  • pronounced as //z// was not lost in single-syllable words in southern and central German. Compare PG Germanic languages: miz > OS mi, OE me vs. OHG mir.
  • The OE nominative plural English, Old (ca.450-1100);: -as (ME English, Middle (1100-1500);: -s), OS nominative plural -ōs may be from original accusative plural Germanic languages: -ans, due to the Ingvaeonic Nasal-Spirant law, rather than original nominative plural Germanic languages: -ōz, which would be expected to become *-a (OHG -a, compare ON Norse, Old: -ar).
• Rhotacization: pronounced as //z// > pronounced as //r//.
  • This change also affected Proto-Norse, but only much later. pronounced as //z// and pronounced as //r// were still distinct in the Danish and Swedish dialect of Old Norse, as is testified by distinct runes. (pronounced as //z// is normally assumed to be a rhotic fricative in this language, but there is no actual evidence of this.)
  • PG > Goth Gothic: dius; OE dēor > ModE deer
• Intervocalic ðw > ww.
• Hardening: ð > d, β > v, and ɸ > f.
• West Germanic gemination: single consonants followed by pronounced as //j// except pronounced as //r// became double (geminate). This only affected consonants preceded by a short vowel, because those preceded by a long vowel or by another consonant were never followed by pronounced as //j// due to Sievers' law.
  • PG > OE biddan, habban > ModE bid, have

Ingvaeonic and Anglo-Frisian period

This period is estimated to have lasted only a century or so, the 4th to 5th; the time during which the Franks started to spread south into Gaul (France) and the various coastal people began colonising Britain. Changes in this period affected the Ingvaeonic languages, but not the more southerly Central and Upper German languages. The Ingvaeonic group was probably never homogeneous, but was divided further into Old Saxon and Anglo-Frisian. Old Frankish (and later Old Dutch) was not in the core group, but was affected by the spread of several areal changes from the Ingvaeonic area.

The Anglo-Frisian languages shared several unique changes that were not found in the other West Germanic languages. The migration to Britain caused a further split into early Old English and early Old Frisian.

• Ingvaeonic nasal spirant law: Loss of nasals before fricatives, with nasalization and compensatory lengthening of the preceding vowel. Hence PG Germanic languages: munþaz became ModG Mund but in Ingvaeonic dialects first became Germanic languages: mų̄þa. Old English then denasalised the vowels, giving OE English, Old (ca.450-1100);: mūþ > ModE "mouth".
  • Following this pronounced as //ɑ̃ː// > pronounced as //õː//. PrePG * > PG Germanic languages: tanþs > Germanic languages: tą̄þ > Germanic languages: tǭþ > OE English, Old (ca.450-1100);: tōþ > ModE "tooth". (ModG Zahn < OHG zant.) This also applied to pronounced as //ɑ̃ː// arising earlier in Proto-Germanic: PG Germanic languages: þanhtǭ > Late PG Germanic languages: þą̄htǭ > OE English, Old (ca.450-1100);: þōhte > ModE "(I) thought".
• Anglo-Frisian brightening:
  • Fronting of pronounced as //ɑ// to pronounced as //æ// (unless followed by a geminate, by a back vowel in the next syllable, and in certain other cases). Hence OE dæġ pronounced as //dæj// "day", plural dagas pronounced as //dɑɣɑs// "days" (dialectal ModE "dawes"; compare ModE "dawn" < OE dagung pronounced as //dɑɣuŋɡ//).
  • This does not affect nasal pronounced as //ɑ̃//. And since this is a back vowel, pronounced as //ɑ// in a preceding syllable was prevented from being fronted as well. This created an alternation between the infinitive in *-aną and strong past participle in *-ana (< PG *anaz), where the former became -an in OE but the latter became *-ænæ > -en.
  • Fronting of pronounced as //ɑː// to pronounced as //æː// (generally, unless pronounced as //w// followed).
• Final-syllable pronounced as //æ//, pronounced as //ɑ// and pronounced as //ɑ̃// are lost.
  • No attested West Germanic languages show any reflexes of these vowels. However, the way it affected the fronting of pronounced as //ɑ// as described above shows that at least pronounced as //ɑ̃// was retained into the separate history of Anglo-Frisian.

Old English period

See main article: Phonological history of Old English. This period is estimated to be c. AD 475–900. This includes changes from the split between Old English and Old Frisian (c. AD 475) up through historic early West Saxon of AD 900:

• Breaking of front vowels.
  • Most generally, before pronounced as //x, w//, and pronounced as //r, l// + consonant (assumed to be velarized pronounced as /[rˠ, lˠ]/ in these circumstances), but exact conditioning factors vary from vowel to vowel.
  • Initial result was a falling diphthong ending in pronounced as //u//, but this was followed by diphthong height harmonization, producing short pronounced as //æ̆ɑ̆//, pronounced as //ĕŏ//, and pronounced as //ĭŭ// from short pronounced as //æ//, pronounced as //e//, and pronounced as //i//. Long pronounced as //æɑ//, pronounced as //eo//, and pronounced as //iu// came from long pronounced as //æː//, pronounced as //eː//, and pronounced as //iː//.
    • Written ea, eo, io, where length is not distinguished graphically.
  • Result in some dialects, for example Anglian, was back vowels rather than diphthongs. West Saxon ceald; but Anglian cald > ModE cold.
• Diphthong height harmonization: The height of one element of each diphthong is adjusted to match that of the other.
  • pronounced as //ɑi// > pronounced as //ɑː// through this change, possibly through an intermediate stage pronounced as //ɑæ//. PG Germanic languages: stainaz > OE English, Old (ca.450-1100);: stān > ModE stone.
  • pronounced as //ɑu// was first fronted to pronounced as //æu// and then harmonized to pronounced as //æɑ//. PG Germanic languages: draumaz > OE "joy" (cf. ModE dream, ModG Traum). PG Germanic languages: dauþuz > OE English, Old (ca.450-1100);: dēaþ > ModE death (Goth Gothic: dáuþus, ModG Tod). PG Germanic languages: augō > OE > ModE eye (Goth Gothic: áugo, ModG Auge).
  • pronounced as //eu// is harmonized to pronounced as //eo//.
• A-restoration: Short pronounced as //æ// is backed to pronounced as //ɑ// when a back vowel follows in the next syllable.
  • This produces alternations such as OE dæġ "day", pl. dagas (cf. dialectal dawes "days").
• Palatalization of velar consonants: pronounced as //k, ɡ, ɣ, sk// were palatalized to pronounced as //tʃ, dʒ, ʝ, ʃ// in certain complex circumstances. A similar palatalization happened in Frisian, but by this point the languages had split up; the Old English palatalization must be ordered after Old-English-specific changes such as a-restoration.
  • Generally, the velar stops pronounced as //k, ɡ// were palatalized before pronounced as //i(ː)// or pronounced as //j//; after pronounced as //i(ː)// when not before a vowel; and pronounced as //k// was palatalized at the beginning of a word before front vowels. (At this point, there was no word-initial pronounced as //ɡ//.)
  • pronounced as //ɣ// was palatalized in somewhat broader circumstances: By any following front vowel, as well as by a preceding front vowel when a vowel did not immediately follow the pronounced as //ɣ//.
  • pronounced as //ʝ// later becomes pronounced as //j//, but not before the loss of older pronounced as //j// below.
  • pronounced as //sk// is palatalized in almost all circumstances. PG Germanic languages: skipaz > ModE ship (cf. skipper < Dutch schipper, where no such change happened), but West Frisian skip. PG Germanic languages: skurtijaz > OE scyrte > ModE shirt, but > ON skyrt > ModE skirt. An example of retained pronounced as //sk// is PG Germanic languages: aiskōną > OE ascian > ModE ask; there is evidence that OE ascian was sometimes rendered metathetized to acsian, which is the presumed origin of ModE ask (and also of the modern dialectal pronunciation ax).
• Palatal diphthongization: Initial palatal pronounced as //j//, pronounced as //tʃ//, pronounced as //ʃ// trigger spelling changes of a > ea, e > ie. It is disputed whether this represents an actual sound change or merely a spelling convention indicating the palatal nature of the preceding consonant (written g, c, sc were ambiguous in OE as to palatal pronounced as //j//, pronounced as //tʃ//, pronounced as //ʃ// and velar pronounced as //ɡ// or pronounced as //ɣ//, pronounced as //k//, pronounced as //sk//, respectively).
  • Similar changes of o > eo, u > eo are generally recognized to be merely a spelling convention. Hence WG pronounced as //juŋɡ// > OE geong pronounced as //juŋɡ// > ModE "young"; if geong literally indicated an pronounced as //ɛ̆ɔ̆// diphthong, the modern result would be *yeng. It is disputed whether there is Middle English evidence of the reality of this change in Old English.
• i-mutation: All back vowels were fronted before a pronounced as //i, j// in the next syllable, and front vowels were raised.
  • pronounced as //ɑ(ː)// > pronounced as //æ(ː)// (but pronounced as //ɑ// > pronounced as //e// before pronounced as //m// or pronounced as //n//);
  • pronounced as //o(ː)// > pronounced as //ø(ː)// > pronounced as //e(ː)//;
  • pronounced as //u(ː)// > pronounced as //y(ː)//;
  • pronounced as //æa//, pronounced as //eo// > pronounced as //iy// > pronounced as //yː//; this also applied to the equivalent short diphthongs.
  • Short pronounced as //e// > pronounced as //i// by an earlier pan-Germanic change under the same circumstances; often conflated with this change.
  • This had dramatic effects in inflectional and derivational morphology, e.g. in noun paradigms (fōt "foot", pl. fēt "feet"); verb paradigms (bacan "to bake", bæcþ "he bakes"); nominal derivatives from adjectives (strang "strong", strengþ(u) "strength"), from verbs (cuman "to come", cyme "coming"), and from other nouns (fox "fox", fyxenn "vixen"); verbal derivatives (fōda "food", fēdan "to feed"); comparative adjectives (eald "old", ieldra "older, elder"). Many echoes of i-mutation are still present in the modern language.
• Close-vowel loss: Loss of word-final pronounced as //i// and pronounced as //u// (also from earlier pronounced as //oː//) except when following a short syllable (i.e. one with a short vowel followed by a single consonant.) For example, PIE * > PG Germanic languages: sunuz > OE sunu "son (nom. sing.)", PIE * > PG Germanic languages: fehu > OE feohu "cattle (nom. sing.)", PIE * > PG Germanic languages: winiz > OE ƿine "friend (nom. sing.)", but PrePG * > PG Germanic languages: fōtiz > WG Germanic languages: fø̄ti > OE English, Old (ca.450-1100);: fēt "foot (nom. pl.)".
• Loss of pronounced as //j// and pronounced as //ij// following a long syllable.
  • A similar change happened in the other West Germanic languages, although after the earliest records of those languages.
  • This did not affect the new pronounced as //j// (< pronounced as //ʝ//) formed from palatalisation of PG pronounced as /
    • /ɣ/
    /, suggesting that it was still a palatal fricative at the time of the change. For example, PG Germanic languages: wrōgijanan > early OE *pronounced as /wrøːʝijan/ > OE ƿrēġan (pronounced as //wreːjan//).
  • Following this, PG pronounced as /
    • /j/
    / occurred only word-initially and after pronounced as //r// (which was the only consonant that was not geminated by pronounced as //j// and hence retained a short syllable).
• H-loss: Proto-Germanic pronounced as //x// is lost between vowels, and between pronounced as //l, r// and a vowel. The preceding vowel is lengthened.
  • This leads to alternations such as eoh "horse", pl. ēos, and ƿealh "foreigner", pl. ƿēalas.
• Vowel assimilation: Two vowels in hiatus merge into a long vowel.
  • Some examples come from h-loss. Others come from loss of pronounced as //j// or pronounced as //w// between vowels, e.g. PG frijōndz > OE frīond > frēond "friend"; PG saiwimiz "sea (dat. pl.)" > *sǣƿum > OE sǣm.
• Back mutation: Short e, i and (in Mercian only) a are sometimes broken to short eo, io, and ea when a back vowel follows in the next syllable.
  • Hence seofon "seven" < PG *sebun, mioluc, meoluc "milk" < PG *meluks.
• Palatal umlaut: Short e, eo, io become i (occasionally ie) before hs, ht.
  • Hence riht "right" (cf. German recht), siex "six" (cf. German sechs).
• Vowel reductions in unstressed syllables:
  • pronounced as //oː// became pronounced as //ɑ// in final syllables, but usually appears as o in medial syllables (although a and u both appear).
  • pronounced as //æ// and pronounced as //i// (if not deleted by high-vowel loss) became pronounced as //e// in final syllables.
  • pronounced as //u// normally became pronounced as //o// in a final syllable except when absolutely word-final.
  • In medial syllables, short pronounced as //æ, a, e// are deleted; short pronounced as //i, u// are deleted following a long syllable but usually remain following a short syllable (except in some present-tense verb forms), merging to pronounced as //e// in the process; and long vowels are shortened.
• pronounced as //ø, øː// are unrounded to pronounced as //e, eː//, respectively. This occurred within the literary period.
  • Some Old English dialects retained the rounded vowels, however.
• Early pre-cluster shortening: Vowels were shortened when falling immediately before either three consonances or the combination of two consonants and two additional syllables in the word.
  • Thus, OE gāst > ModE ghost, but OE găstliċ > ModE ghastly (ā > ă) and OE crīst > ModE Christ, but OE crĭstesmæsse > ModE Christmas (ī > ĭ).
  • Probably occurred in the seventh century as evidenced by eighth century Anglo-Saxon missionaries' translation into Old Low German, "Gospel" as Gotspel, lit. "God news" not expected *Guotspel, "Good news" due to gōdspell > gŏdspell.
• pronounced as //ĭŭ// and pronounced as //iu// were lowered to pronounced as //ĕŏ// and pronounced as //eo// between 800 and 900 AD.
• Initial pronounced as //ɣ// became pronounced as //ɡ// in late Old English. This occurred within the literary period, as evidenced by shifting patterns in alliterative verse.

Changes by time period from Middle English to American-British split

The Middle English Period

This period is estimated to be c. 900–1400.

• Homorganic lengthening: Vowels were lengthened before pronounced as //ld//, pronounced as //mb//, pronounced as //nd//, pronounced as //rd//, probably also pronounced as //ŋɡ//, pronounced as //rl//, pronounced as //rn//, when not followed by a third consonant or two consonants and two syllables.
  • This probably occurred around AD 1000.
  • Later on, many of these vowels were shortened again; but evidence from the Ormulum shows that this lengthening was once quite general.
  • Remnants persist in the Modern English pronunciations of words such as child (but not children, since a third consonant follows), field (plus yield, wield, shield), old (but not alderman as it is followed by at least two syllables), climb, find (plus mind, kind, bind, etc.), long and strong (but not length and strength), fiend, found (plus hound, bound, etc.).
• Pre-cluster shortening: Vowels were shortened when followed by two or more consonants, except when lengthened as above.
  • This occurred in two stages, the first stage occurring already in late Old English and affecting only vowels followed by three or more consonants, or two or more consonants when two syllables followed (an early form of trisyllabic laxing).
• Diphthong smoothing: Inherited height-harmonic diphthongs were monophthongized by the loss of the second component, with the length remaining the same.
  • pronounced as //æ̆ɑ̆// and pronounced as //æɑ// initially became pronounced as //æ// and pronounced as //æː//.
  • pronounced as //ĕŏ// and pronounced as //eo// initially became pronounced as //ø// and pronounced as //øː//.
• Middle English stressed vowel changes:
  • pronounced as //æː// (from Old English pronounced as //æː, æɑ//) and pronounced as //ɑː// became pronounced as //ɛː// and pronounced as //ɔː//, respectively.
  • pronounced as //æ// (from Old English pronounced as //æ, æ̆ɑ̆//) and pronounced as //ɑ// merged into pronounced as //a//.
  • New front-rounded pronounced as //ø// and pronounced as //øː// (from Old English pronounced as //ĕŏ, eo//) were unrounded to pronounced as //e// and pronounced as //eː//.
  • pronounced as //y// and pronounced as //yː// were unrounded to pronounced as //i// and pronounced as //iː//.
• -dər > -ðər. This also occurred after the final reduction.
• pronounced as //ɣ// became pronounced as //w// or pronounced as //j//, depending on surrounding vowels.
• New diphthongs formed from vowels followed by pronounced as //w// or pronounced as //j// (including from former pronounced as //ɣ//).
  • Length distinctions were eliminated in these diphthongs, yielding diphthongs pronounced as //ai, ɛi, ei, au, ɛu, eu, iu, ɔu, ou// plus pronounced as //ɔi, ui// borrowed from French.
  • Middle English breaking: Diphthongs also formed by the insertion of a glide pronounced as //w// or pronounced as //j// (after back and front vowels, respectively) preceding pronounced as //x//.
• Mergers of new diphthongs:
  • Early on, high-mid diphthongs were raised: pronounced as //ei// merged with pronounced as //iː// (hence eye < OE ēġe rhymes with rye < *riġe < OE ryġe), pronounced as //ou// merged with pronounced as //uː// and pronounced as //eu// merged with pronounced as //iu// (hence rue < OE hrēoƿan rhymes with hue < OE hīƿ and new < OE nīƿe).
  • In Late Middle English, pronounced as //ai// and pronounced as //ɛi// merge as pronounced as //ɛi//, so that vain and vein are homophones (the vein–vain merger).
• Trisyllabic laxing: Shortening of stressed vowels when two syllables followed.
  • This results in pronunciation variants in Modern English such as divine vs divinity and south vs. southern (OE sūðerne).
• Middle English open syllable lengthening: Vowels were usually lengthened in open syllables (13th century), except when trisyllabic laxing would apply.
• Reduction and loss of unstressed vowels: Remaining unstressed vowels merged into pronounced as //ə//.
  • Starting around 1400 AD, pronounced as //ə// is lost in final syllables.
• Initial clusters pronounced as //hɾ//, pronounced as //hl//, pronounced as //hn// were reduced by loss of pronounced as //h//.
• Voiced fricatives became independent phonemes through borrowing and other sound changes.
• pronounced as //sw// before back vowel becomes pronounced as //s//; pronounced as //mb// becomes pronounced as //m//.
  • Modern English sword, answer, lamb.
  • pronounced as //w// in swore is due to analogy with swear.
• The pronounced as //t͡s// cluster, present in words imported from Norman, is deaffricated, and merges with pronounced as //s// (which had perhaps been apical in medieval times, as in closely related Dutch and Low German), thus merging sell and cell.
  • But unlike French, pronounced as //t͡ʃ// and pronounced as //d͡ʒ// are fully preserved.
• In late Middle English, the extremely rare word-initial cluster fn- became sn- (EME fnesen > LME snezen > ModE sneeze).
  • It has been suggested that the change could be due to a misinterpretation of the uncommon initial sequence fn- as ſn- (sn- written with a long s).^[1]

Up to Shakespeare's English

This period is estimated to be c. AD 1400–1600.

• H-loss completed: pronounced as //x// (written gh) lost in most dialects, so that e.g. taught and taut become homophones, likewise bow (meaning "bend") and bough. However, when preceded by /u/) (including in diphthongs), it sometimes got labialized to /f/, as in enough.
• pronounced as //al// and pronounced as //ɔl// when not followed by a vowel undergo mutations:
  • Before pronounced as //k//, a coronal consonant or word-finally, they are diphthongized to pronounced as //aul// and pronounced as //ɔul//. (By later changes, they become pronounced as //ɔːl// and pronounced as //oul//, as in modern salt, tall, bolt, roll.) After this, the combinations pronounced as //aulk// and pronounced as //ɔulk// lose their pronounced as //l// in most accents, affecting words like talk, caulk, and folk. Words acquired after this change (such as talc) were not affected.
  • Before pronounced as //f, v//, the pronounced as //l// becomes silent, so that half and calf are pronounced with pronounced as //af//, and salve and halve are pronounced with pronounced as //av//. pronounced as //ɔlv// is exempt, so that solve keeps its pronounced as //l//. pronounced as //ɔlf// is not wholly exempt, as the traditional pronunciation of golf was pronounced as /[ɡɔf]/.
  • Before pronounced as //m//, pronounced as //al, ɔl// become pronounced as //ɑː, oː//, as in alms, balm, calm, palm; Holmes.
  • Some words have irregular pronunciations, e.g. from non-standard dialects (salmon) or spelling pronunciations (falcon in American English).
• Short pronounced as //i, u// develop into lax pronounced as //ɪ, ʊ//
• Great Vowel Shift; all long vowels raised or diphthongized.
  • pronounced as //aː, ɛː, eː// become pronounced as //ɛː, eː, iː//, respectively.
  • pronounced as //ɔː, oː// become pronounced as //oː, uː//, respectively.
  • pronounced as //iː, uː// become pronounced as //əi, əu// or pronounced as //ei, ou//, later pronounced as //ai// and pronounced as //au//.
  • New pronounced as //ɔː// developed from old pronounced as //au// (see below).
    • Thus, pronounced as //ɔː, oː, uː, au// effectively rotated in-place.
  • Later, the new pronounced as //ɛː, eː// are shifted again to pronounced as //eː, iː// in Early Modern English, causing merger of former pronounced as //eː// with pronounced as //iː//; but the two are still distinguished in spelling as ea, ee. the meet-meat merger (see below)
• Initial cluster reductions:
  • pronounced as //wr// merges into pronounced as //r//; hence rap and wrap become homophones.
• Doubled consonants reduced to single consonants.
• Loss of most remaining diphthongs.
  • pronounced as //au// became pronounced as //ɔː//, merging with the vowel in broad and the pronounced as //ɔː// of the lot–cloth split below.
  • The long mid mergers: pronounced as //ɛi, ɔu// are raised to pronounced as //ei, ou//, eventually merging with pronounced as //eː, oː//, so that pane and pain, and toe and tow, become homophones in most accents.
  • The above two mergers did not occur in many regional dialects as late as the 20th century (e.g. Northern England, East Anglia, South Wales, and even Newfoundland).
  • pronounced as //y, ɛu, iu// merge to pronounced as /[ɪʊ̯]/,^[2] so that dew (EME pronounced as //dɛu// < OE dēaƿ), duke (EME pronounced as //dyk// < Old French duc pronounced as //dyk//) and new (EME pronounced as //niu// < OE nīƿe) now have the same vowel.
    • This pronounced as //ɪu// would become pronounced as //juː// in standard varieties of English, and later still pronounced as //uː// in some cases through "Yod-dropping".
    • pronounced as //iu// remains in Welsh English and some other non-standard varieties.
  • pronounced as //ɔi// and pronounced as //ui// merge to /pronounced as /ink/pronounced as /ink// (today), the only Middle English diphthong that remains in the modern standard English varieties.

Up to the American–British split

This period is estimated to be c. AD 1600–1725.

• At some preceding time after Old English, all pronounced as /[r]/ become pronounced as /[ɹ]/.
  • Much of Scottish English has pronounced as /[r]/ consistently.
• /p t k/ develop aspirated allophones /pʰ tʰ kʰ/ when they occur alone at the beginning of stressed syllables.
• Initial cluster reductions:
  • pronounced as //ɡn, kn// both merge into pronounced as //n//; hence gnat and Nat become homophones; likewise not and knot.
• The foot–strut split: In southern England, pronounced as //ʊ// becomes unrounded and eventually lowered unless preceded by a labial and followed by a non-velar. This gives put pronounced as /[pʊt]/ but cut pronounced as /[kʌt]/ and buck pronounced as /[bʌk]/. This distinction later become phonemicized by an influx of words shortened from pronounced as //uː// to pronounced as //ʊ// both before (flood, blood, glove) and after (good, hood, book, soot, took) this split.
• Ng-coalescence: Reduction of pronounced as //ŋɡ// in most areas produces new phoneme pronounced as //ŋ//.
• In some words, pronounced as //tj, sj, dj, zj// coalesce to produce pronounced as //tʃ, ʃ, dʒ, ʒ// with /ʒ/ being a new phoneme, a sound change known as yod-coalescence, a type of palatalization: nature, mission, procedure, vision.
  • These combinations mostly occurred in borrowings from French and Latin.
  • Pronunciation of -tion was pronounced as //sjən// from Old French pronounced as //sjon//, thus becoming pronounced as //ʃən//.
  • This sound mutation still occurs allophonically in Modern English: did you pronounced as //ˈdɪdjuː// → pronounced as /[ˈdɪdʒuː]/ didjou.
• /ɔ/ as in lot, top, and fox, is lowered towards /ɒ/.
• Long vowels pronounced as //eː, uː//, from ME pronounced as //ɛː, oː//, inconsistently shortened, especially before pronounced as //t, d, θ, ð//: sweat, head, bread, breath, death, leather, weather
  • Shortening of pronounced as //uː// occurred at differing time periods, both before and after the centralizing of pronounced as //ʊ// to pronounced as //ʌ//; hence blood pronounced as //blʌd// versus good pronounced as //ɡʊd//: also foot, soot.
• The Meet–meat merger /eː/ (ea) raises to /iː/ (ee) Thus Meet and meat become homophones in most accents. Words with (ea) that were shortened (see above) avoided the merger, also some words like steak and great simply remained with an /eː/ (which later becomes /eɪ/ in most varieties) merging with words like name, so now death, great, and meat have three different vowels.
• Changes affect short vowels in many varieties before an pronounced as //r// at the end of a word or before a consonant
  • pronounced as //a// as in start and pronounced as //ɔ// as in north are lengthened.
  • pronounced as //ɛ, ɪ, ʌ, ʊ// (the last of these often deriving from earlier pronounced as //oːr// after pronounced as /ink/, as in worm and word) merge before pronounced as //r//, so all varieties of ModE except for some Scottish English and some Irish English have the same vowel in fern, fir and fur.
  • Also affects vowels in derived forms, so that starry no longer rhymes with marry.
• pronounced as //a//, as in cat and trap, fronted to pronounced as /[æ]/ in many areas. In certain other words it becomes pronounced as //ɑː//, for example father pronounced as //ˈfɑːðər//. pronounced as //ɑː// is actually a new phoneme deriving from this and words like calm (see above).
  • Most varieties of Northern England English, Welsh English and Scottish English retain pronounced as /[a]/ in cat, trap etc.
• The lot–cloth split: in some varieties, lengthening of pronounced as //ɔ// before voiced velars (pronounced as //ŋ//, pronounced as //ɡ//) (American English only) and voiceless fricatives (pronounced as //s//, pronounced as //f//, pronounced as //θ//). Hence American English long, dog, loss, cloth, off with pronounced as //ɔː// (except in dialects with the cot–caught merger where the split is made completely moot).
• pronounced as //uː// becomes pronounced as //ʊ// in many words spelt oo: for example, book, wool, good, foot. This is partially resisted in the northern and western variants of English English, where words ending in -ook might still use pronounced as //uː//.

Changes by time period from after American-British split to after World War II

After American–British split, up to World War II

This period is estimated to be c. AD 1725–1945.

• Split into rhotic and non-rhotic accents: syllable-final pronounced as //r// is lost in much of the English of England, with exceptions including West Country English and Lancashire dialect.
  • The loss of coda pronounced as //r// causes significant changes to preceding vowels:
    • pronounced as //ər// merges with pronounced as //ə//
    • pronounced as //aɪr, aʊr, ɔɪr// become pronounced as //aɪə, aʊə, ɔɪə//
    • pronounced as //ær, ɒr// (phonetically pronounced as /[ɑːɹ, ɔːɹ]/) become long vowels, pronounced as //ɑː, ɔː//.
    • All other short vowels plus coda pronounced as //r// merge as a new phoneme, the long mid-central vowel pronounced as //ɜː//.
    • Long vowels with a coda pronounced as //r//, pronounced as //eːr, iːr, oːr, uːr//, become new centering diphthongs, pronounced as //ɛə, ɪə, ɔə, ʊə//.
    • Long vowels before intervocalic pronounced as //r// are also diphthongised, thus dairy pronounced as //ˈdɛər.ɪ// from earlier pronounced as //ˈdeː.rɪ//.
  • The Southern Hemisphere varieties of English (Australian, New Zealand, and South African) are also non-rhotic.
  • Non-rhotic accents of North American English include New York City, Boston, and older Southern.
• Unrounding of : pronounced as //ɒ// as in lot and bother is unrounded in Norwich, the West Country, in Hiberno-English and most of North American English
  • The Boston accent is an exception where the vowel is still rounded.
  • In North American English, pronounced as //ɒ// is typically also lengthened to merge with pronounced as //ɑː// in father, resulting in the father–bother merger: so that most North American dialects only have the vowel pronounced as //ɑː//.
    • Out of North American dialects that have unrounded, the only notable exception is New York City.
• The trap–bath split: in Southern England pronounced as //æ// inconsistently becomes pronounced as //ɑː// before pronounced as //s, f, θ// and pronounced as //n// or pronounced as //m// followed by another consonant.
  • Hence RP has pass, glass, grass, class with pronounced as //ɑː// but mass, crass with pronounced as //æ//.
  • All six words rhyme in most American, Scottish English and Northern England English.
• The long vowels pronounced as //eː oː// from the Great Vowel Shift become diphthongs pronounced as //eɪ oʊ// in many varieties of English, though not in Scottish and Northern England English.
• Voicing of pronounced as //ʍ// to pronounced as //w// results in the wine–whine merger in most varieties of English, aside from Scottish, Irish, Southern American, and New England English.
• In American, Canadian, Australian and to some degree New Zealand English, pronounced as //t, d// are flapped or voiced to pronounced as /[ɾ]/ between vowels.
  • Generally, between vowels or the syllabic consonants pronounced as /[ɹ̩, l̩, m̩]/, when the following syllable is completely unstressed: butter, bottle, bottom pronounced as /[ˈbʌɾɹ̩ ˈbɑːɾl̩ ˈbɑːɾm̩]/.
  • But pronounced as //d// and pronounced as //t// before syllabic pronounced as /[n̩]/ is pronounced as a glottal stop, so cotton pronounced as /[ˈkɑːʔn̩]/.
• Happy-tensing (the term is from Wells 1982): final lax pronounced as /[ɪ]/ becomes tense pronounced as /[i]/ in words like happ. Absent from some dialects like Southern American English, Traditional RP, cultivated South African English, most forms of Northern England English (excluding Scouse and Geordie) and to some degree Scottish English.
• Line–loin merger: merger between the diphthongs pronounced as //aɪ// and pronounced as //ɔɪ// in some accents of Southern England English, Hiberno-English, Newfoundland English, and Caribbean English.
• H-dropping begins in England and Welsh English, but this does not affect the upper-class southern accent that developed into Received Pronunciation, nor does it affect the far north of England or East Anglia.
• Reversal of the lot-cloth split in British English so words like cloth revert to being pronounced with pronounced as //ɒ//. The split survives in American English.

After World War II

Some of these changes are in progress.

• Restoration of post-vocalic pronounced as //r// in some non-rhotic accents of Southern American English as well as (more gradually) in New York City English and Eastern New England English.
• Changes to the low front vowel pronounced as //æ//
  • /æ/ raising: raising, lengthening or diphthongization of pronounced as /[æ]/ in some varieties of American English in various contexts, especially before nasal consonants, resulting in pronounced as /[eə, ɪə, æɪ]/. Some linguistics research suggests that pronounced as /æ/ raising existed since the American colonial era, due to relic evidence of this feature in some of the Northern and Midland U.S.
  • Bad–lad split: the lengthening of pronounced as /[æ]/ to pronounced as /[æː]/ in some words, found especially in Australian English and to a degree in Southern English English.
  • Raising pronounced as /[æ]/ to pronounced as /[ɛ]/ in New Zealand English and South African English.
  • Lowering to pronounced as /[a]/ in Received Pronunciation, Canadian English, Western American English, and Australian English (except before nasal consonants in the latter two).^[3]
• Changes to the non-high back vowels pronounced as //ɒ// and pronounced as //ɔː//:
  • pronounced as //ɒ// is raised to pronounced as /[ɔ]/ and pronounced as //ɔː// is raised to pronounced as /[oː]/ in Southern England English,^[4] Australian English and New Zealand English.
  • Cot–caught merger: lowering of pronounced as //ɔ// to pronounced as //ɑ// in Western American English and some dialects in New England and the Midland region. This sound change is still in progress.
• Fronting of high back vowels /uː/, /oʊ/, /ʌ/ and /ʊ/.
  • In many varieties of English, pronounced as //uː// is fronted to pronounced as /[u̟]/, pronounced as /[ʉw]/, or pronounced as /[ɵu̯]/
    • Resistance occurs in Northern American English and New York City English.
  • In Australian English, New Zealand English, most English of England and some American English, pronounced as //oʊ// is fronted to pronounced as /[ɵw]/, pronounced as /[əw]/, or pronounced as /[ɛw]/
    • Resistance occurs in most varities of Northern England English,^[5] as well as Scottish English,^[6] Northern American English and New York City English.
  • In many varieties pronounced as //ʌ// is fronted to pronounced as /[ʌ̟], [ɜ], [ə], [ɐ]/.
  • In Southern England English, pronounced as //ʊ// is fronted to pronounced as /[ɵ]/.
• Lock–loch merger: the replacement of pronounced as /[x]/ with pronounced as /[k]/ among some younger Scottish English speakers from Glasgow.^[7] (Department of Language and Linguistics | University of Essex)
• Pin–pen merger: the raising of pronounced as //ɛ// to pronounced as //ɪ// before nasal consonants in Southern American English and southwestern varieties of Hiberno-English.
• Horse-hoarse merger

pronounced as //ɔr// and pronounced as //or// merge in many varieties of English

• Vowel mergers before intervocalic pronounced as //r// in most of North America (resistance occurs mainly on the east coast):
  • Mary–marry–merry merger: pronounced as //ɛər// and pronounced as //ær// merge to pronounced as //ɛr//.
  • Hurry-furry merger: pronounced as //ʌr// and pronounced as //ɜr// merge to pronounced as /[ɚ]/.
  • Mirror-nearer merger pronounced as //ɪr// and pronounced as //ɪər// merge or are very similar, the merged vowel can be quite variable.
• T-glottalization becomes increasingly widespread in Great Britain.
• Various treatments of the th sounds, the dental fricatives pronounced as //θ, ð//:
  • Th-fronting: merger with the labiodental fricatives pronounced as //f, v//
  • Th-stopping: shift to dental stops pronounced as /[t̪, d̪]/, or merger with alveolar stops pronounced as /[t, d]/
  • Th-debuccalization: lenition to pronounced as /[h]/
  • Th-alveolarization: merger with alveolar fricatives pronounced as /[s, z]/
• L-vocalization: pronounced as /[l]/ changes to an approximant or vowel, such as pronounced as /[w]/, pronounced as /[o]/ or pronounced as /[ʊ]/. This occurs in Estuary English and other dialects.
• Yod-dropping: loss of pronounced as //j// in some consonant clusters. Though it occurs in some environments in many British English dialects, it is most extensive in American and (in younger speakers) Canadian English.
• Northern Cities Vowel Shift in Inland Northern American English:
  • raising and tensing of pronounced as //æ// (in reversal^{[8] [9] [10]} in many locations before non-nasal consonants)
  • fronting of pronounced as //ɑː// (also somewhat in reversal)
  • lowering of pronounced as //ɔː//
  • backing and lowering of pronounced as //ɛ//
  • backing of pronounced as //ʌ//
  • lowering and backing of pronounced as //ɪ//
• Changes to centering diphthongs in non-rhotic varieties of English (England and Australia):
  • pronounced as //ɪə, ɛə, ɑə, ɔə// smooth to pronounced as /[ɪː, ɛː, ɑː, ɔː~oː]/: near, square, start, force.
  • pronounced as /[ʊə]/ either
    • smooths (and possibly also fronts) to pronounced as /[ʊː~ɵː]/,
    • breaks to pronounced as /[uːə]/,
    • lowers and merges with pronounced as //ɔː// (pour–poor merger):
  • Triphthongs pronounced as //aɪə/, /aʊə// smooth to pronounced as /[aː]/ or pronounced as /[ɑː]/ (tower–tire, tower–tar and tire–tar mergers).
• Other changes to diphthongs in Received Pronunciation:^[11]
  • /eɪ/ is lowered to [ɛɪ].
  • /aɪ/ is retracted to [ɑɪ].
  • /ɔɪ/ is raised to [oɪ].
  • /aʊ/ is fronted from [ɑʊ] to [aʊ].

Examples of sound changes

The following table shows a possible sequence of changes for some basic vocabulary items, leading from Proto-Indo-European (PIE) to Modern English. The notation ">!" indicates an unexpected change, whereas the simple notation ">" indicates an expected change. An empty cell means no change at the given stage for the given item. Only sound changes that had an effect on one or more of the vocabulary items are shown.

	one	two	three	four	five	six	seven	mother	heart	hear	foot	feet
Proto-Indo-European			(fem.)
Centumization
Pre-Germanic unexpected changes (perhaps P-Celtic or P-Italic influences)		>! pronounced as /dwóy/	>! pronounced as /tríh₂s/	>! pronounced as /petwṓr/	>! pronounced as /pémpe/		>! pronounced as /sepḿ̥d/	>! pronounced as /meh₂tḗr/	>! pronounced as /kérdō/			pronounced as /pṓdes/
Sonorant epenthesis							sepúmd
Final overlong vowels									pronounced as /kérdô/
Laryngeal loss			pronounced as /trī́s/					pronounced as /mātḗr/		pronounced as /kowsyónom/
Loss of final nonhigh vowels					pronounced as /pemp/
Grimm's Law		pronounced as /twoi/	pronounced as /þrī́s/	pronounced as /feþwṓr/	pronounced as /fémf/	pronounced as /sehs/	pronounced as /sefúmt/	pronounced as /māþḗr/	pronounced as /hértô/	pronounced as /housjónom/	pronounced as /fṓts/	pronounced as /fṓtes/
Verner's Law	pronounced as /oinoz/		pronounced as /þrīz/	pronounced as /feðwōr/			pronounced as /seβumt/	pronounced as /māðēr/		pronounced as /houzjonom/		pronounced as /fōtez/
Unstressed syllables: pronounced as /owo > ō, ew > ow, e > i, ji > i/												pronounced as /fōtiz/
o > a, ō > ā, ô > â	pronounced as /ainaz/	pronounced as /twai/		pronounced as /feðwār/					pronounced as /hertâ/	pronounced as /hauzjanam/	pronounced as /fāts/	pronounced as /fātiz/
Final -m > -n										pronounced as /hauzjanan/
m > n before dental							pronounced as /seβunt/
Final -n > nasalization										pronounced as /hauzjaną/
Loss of final -t							pronounced as /seβun/
Sievers' Law										pronounced as /hauzijaną/
Nasal raising					pronounced as /fimf/
ā > ō, â > ô				pronounced as /feðwōr/				pronounced as /mōðēr/	pronounced as /hertô/		pronounced as /fōts/	pronounced as /fōtiz/
Proto-Germanic form	Germanic languages: ainaz	Germanic languages: twai	Germanic languages: þrīz	Germanic languages: feðwōr	Germanic languages: fimf	Germanic languages: sehs	Germanic languages: seβun	Germanic languages: mōðēr	Germanic languages: hertô	Germanic languages: hauzijaną	Germanic languages: fōts	Germanic languages: fōtiz
Final vowel shortening/loss	Germanic languages: ainz?		Germanic languages: þrīz	Germanic languages: feðwur				Germanic languages: mōðar	Germanic languages: hertō	Germanic languages: hauzijan
Final -z loss	Germanic languages: ain		Germanic languages: þrī									Germanic languages: fōti
Rhotacism: z > r										pronounced as /haurijan/
Intervocalic ðw > ww				Germanic languages: fewwur
Hardening: ð > d, β > v, f pronounced as /[ɸ]/ > pronounced as /[f]/					Germanic languages: finf		Germanic languages: sevun	Germanic languages: mōdar
Morphological changes			>! Germanic languages: þriju						>! Germanic languages: herta		> Germanic languages: fōt
West Germanic pre-form	ain	twai	þriju	fewwur	finf	sehs	sevun	mōdar	herta	haurijan	fōt	fōti
Ingvaeonic (prespirant) nasal loss					pronounced as /fīf/
ai > ā	pronounced as /ān/	pronounced as /twā/
Anglo-Frisian brightening									pronounced as /hertæ/	pronounced as /hæurijan/
I-mutation										pronounced as /heyrijan/		pronounced as /fēti/
Loss of medial -ij-										pronounced as /heyran/
Breaking									pronounced as /hĕŭrtæ/
Diphthong height harmony				pronounced as /feowur/					pronounced as /hĕŏrtæ/	pronounced as /hēran/, pronounced as /hiyran/
Back mutation							pronounced as /sĕŏvun/
Final reduction				pronounced as /feowor/			pronounced as /sĕŏvon/	>! pronounced as /mōdor/	pronounced as /hĕŏrte/			pronounced as /fēt/
Raising: ehs eht > ihs iht						pronounced as /sihs/
hs > ks						pronounced as /siks/
Late OE lowering: iu > eo			pronounced as /þreo/
iy > ȳ										pronounced as /hȳran/
Late Old English spelling	English, Old (ca.450-1100);: ān	English, Old (ca.450-1100);: twā	English, Old (ca.450-1100);: þrēo	English, Old (ca.450-1100);: fēowor	English, Old (ca.450-1100);: fīf	English, Old (ca.450-1100);: six	English, Old (ca.450-1100);: seofon	English, Old (ca.450-1100);: mōdor	English, Old (ca.450-1100);: heorte	English, Old (ca.450-1100);: hēran, hȳran	English, Old (ca.450-1100);: fōt	English, Old (ca.450-1100);: fēt
Middle English (ME) smoothing			pronounced as /θrøː/	pronounced as /føːwor/			pronounced as /søvon/		pronounced as /hørte/
ME final reduction				pronounced as /føːwər/			pronounced as /søvən/	pronounced as /moːdər/	pronounced as /hørtə/	pronounced as /heːrən/
ME pronounced as //aː æː/ > /ɔː ɛː//	pronounced as /ɔːn/	pronounced as /twɔː/
pronounced as //-dər// > pronounced as //-ðər//								pronounced as /moːðər/
ME unexpected (?) vowel changes					>! pronounced as /fiːv-ə/					>! pronounced as /hɛːrən/
ME diphthong changes				>! pronounced as /fowər/
Late ME unrounding			pronounced as /θreː/				pronounced as /sevən/		pronounced as /hertə/
Late Middle English spelling (c. 1350)	English, Middle (1100-1500);: oon	English, Middle (1100-1500);: two	English, Middle (1100-1500);: three	English, Middle (1100-1500);: fower	English, Middle (1100-1500);: five	English, Middle (1100-1500);: six	English, Middle (1100-1500);: seven	English, Middle (1100-1500);: mother	English, Middle (1100-1500);: herte	English, Middle (1100-1500);: heere(n)	English, Middle (1100-1500);: foot	English, Middle (1100-1500);: feet
Late ME final reduction (late 1300s)				>! pronounced as /fowr/	pronounced as /fiːv/				pronounced as /hert/	pronounced as /hɛːr/
Late ME pronounced as //er/ > /ar// (1400s)									pronounced as /hart/
Late ME Great Vowel Shift (c. 1400-1550)	pronounced as /oːn/ >! pronounced as /wʊn/	pronounced as /twoː/	pronounced as /θriː/		pronounced as /fəiv/			pronounced as /muːðər/		pronounced as /heːr/	pronounced as /fuːt/	pronounced as /fiːt/
Early Modern English (EModE) smoothing				pronounced as /foːr/
EModE raising pronounced as //woː/ > /wuː/ > /uː//		pronounced as /tuː/
EModE shortening								pronounced as /mʊðər/
EModE pronounced as //ʊ/ > /ɤ/ > /ʌ//	pronounced as /wʌn/							pronounced as /mʌðər/
EModE shortening											pronounced as /fʊt/
Later vowel shifts				pronounced as /fɔːr/	pronounced as /faiv/	pronounced as /sɪks/			pronounced as /hɑrt/	pronounced as /hiːr/
Loss of -r (regional)				pronounced as /fɔː/				pronounced as /mʌðə/	pronounced as /hɑːt/	pronounced as /hiə/
Modern pronunciation	pronounced as /wʌn/	pronounced as /tuː/	pronounced as /θriː/	pronounced as /fɔː(r)/	pronounced as /faɪv/	pronounced as /sɪks/	pronounced as /sevən/	pronounced as /mʌðə(r)/	pronounced as /hɑrt//pronounced as /hɑːt/	pronounced as /hiːr/hɪː/	pronounced as /fʊt/	pronounced as /fiːt/
	one	two	three	four	five	six	seven	mother	heart	hear	foot	feet

NOTE: Some of the changes listed above as "unexpected" are more predictable than others. For example:

• Some changes are morphological ones that move a word from a rare declension to a more common one, and hence are not so surprising: e.g. *Germanic languages: þrī "three" >! *þriu (adding the common West Germanic feminine ending -u) and Indo-European languages: keːr "heart" (stem Indo-European languages: kerd-) >! Indo-European languages: kérd-oː (change from consonant stem to n-stem).
• Some changes are assimilations that are unexpected but of a cross-linguistically common type, e.g. pronounced as /føːwər/ "four" >! pronounced as /fowər/ where **pronounced as /fewər/ would be expected by normal sound change. Assimilations involving adjacent numbers are especially common, e.g. Indo-European languages: kʷetwṓr "four" >! Indo-European languages: petwṓr by assimilation to Indo-European languages: pénkʷe "five" (in addition, pronounced as //kʷ/ > /p// is a cross-linguistically common sound change in general).
• On the other extreme, the Early Modern English change of pronounced as //oːn// "one" >! pronounced as //wʊn// is almost completely mysterious. Note that the related words alone (< all + one) and only (< one + -ly) did not change.

Summary of vowel developments

Development of Middle English vowels

Monophthongs

This table describes the main historical developments of English vowels in the last 1000 years, beginning with late Old English and focusing on the Middle English and Modern English changes leading to the current forms. It provides a lot of detail about the changes taking place in the last 600 years (since Middle English), while omitting any detail in the Old English and earlier periods. For more detail about the changes in the first millennium AD, see the section on the development of Old English vowels.

This table omits the history of Middle English diphthongs; see that link for a table summarizing the developments.

The table is organized around the pronunciation of Late Middle English c. 1400 AD (the time of Chaucer) and the modern spelling system, which dates from the same time and closely approximates the pronunciation of the time. Modern English spelling originates in the spelling conventions of Middle English scribes and its modern form was largely determined by William Caxton, the first English printer (beginning in 1476).

As an example, the vowel spelled (a) corresponds to two Middle English pronunciations: pronounced as //a// in most circumstances, but long pronounced as //aː// in an open syllable, i.e. followed by a single consonant and then a vowel, notated aCV in the spelling column. (This discussion ignores the effect of trisyllabic laxing.) The lengthened variant is due to the Early Middle English process of open-syllable lengthening; this is indicated by (leng.). Prior to that time, both vowels were pronounced the same, as a short vowel pronounced as //a//; this is reflected by the fact that there is a single merged field corresponding to both Middle English sounds in the Late Old English column (the first column). However, this earlier Middle English vowel pronounced as //a// is itself the merger of a number of different Anglian Old English sounds:

1. the short vowels indicated in Old English spelling as (a), (æ) and (ea);
2. the long equivalents (ā), (ēa), and often (ǣ) when directly followed by two or more consonants (indicated by ā+CC, ǣ+CC, etc.);
3. occasionally, the long vowel (ē) when directly followed by two consonants, particularly when this vowel corresponded to West Saxon Old English (ǣ). (Middle English, and hence Modern English, largely derives from the Anglian dialect of Old English, but some words are derived from the West Saxon dialect of Old English, because the border between the two dialects ran through the London area. The West Saxon dialect, not the Anglian dialect, is the "standard" dialect described in typical reference works on Old English.)

Moving forward in time, the two Middle English vowels pronounced as //a// and pronounced as //aː// correspond directly to the two vowels pronounced as //a// and pronounced as //ɛː//, respectively, in the Early Modern English of c. 1600 AD (the time of Shakespeare). However, each vowel has split into a number of different pronunciations in Modern English, depending on the phonological context. The short pronounced as //a//, for example, has split into seven different vowels, all still spelled (a) but pronounced differently:

1. pronounced as //æ// when not in any of the contexts indicated below, as in man, sack, wax, etc.
2. A vowel pronounced pronounced as //ɑː// in General American (GA) and pronounced as //ɒ// in Received Pronunciation (RP) when preceded by pronounced as //w// and not followed by the velar consonants pronounced as //k/, /ɡ/ or /ŋ//, as in swan, wash, wallow, etc. (General American is the standard pronunciation in the U.S. and Received Pronunciation is the most prestigious pronunciation in Britain. In both cases, these are the pronunciations typically found in news broadcasts and among the middle and upper classes.)
3. pronounced as //ɑːr// (GA) or pronounced as //ɑː// (RP) when followed by a written (r), as in hard, car, etc. (This does not include words like care, where the (a) was pronounced as long pronounced as //aː// in Middle English.)
4. But pronounced as //ɔːr// (GA) or pronounced as //ɔː// (RP) when both preceded by pronounced as //w// and followed by written (r), as in war, swarm, etc.
5. pronounced as //ɔː// when followed by an pronounced as //l// plus either a consonant or the end of a word, as in small, walk, etc. (In the case of walk, talk, chalk, etc. the pronounced as //l// has dropped out, but this is not indicated here. Words like rally, shallow and swallow are not covered here because the pronounced as //l// is followed by a vowel; instead, earlier rules apply. Nor are words like male covered, which had long pronounced as //aː// in Middle English.)
6. pronounced as //ɑː// when followed by pronounced as //lm//, as in palm, calm, etc. (The pronounced as //l// has dropped out in pronunciation.)
7. In RP only, the pronunciation pronounced as //ɑː// is often found when followed by an unvoiced fricative, i.e. pronounced as //f//, pronounced as //s// or pronounced as //θ// (but not pronounced as //ʃ//), as in glass, after, path, etc. This does not apply to GA and also unpredictably does not affect a number of words of the same form, e.g. crass, math, etc.

Diphthongs

This table describes the main developments of Middle English diphthongs, starting with the Old English sound sequences that produced them (sequences of vowels and g, h or ƿ) and ending with their Modern English equivalents. Many special cases have been ignored.

Development of Old English vowels

See also

• English language
• History of English
• English phonology
• Phonological history of English consonants
  • Phonological history of English consonant clusters
• Phonological history of English vowels
  • Phonological history of English short A
  • Phonological history of English low back vowels
  • Phonological history of English high back vowels
  • Phonological history of English high front vowels
  • English-language vowel changes before historic /r/
  • English-language vowel changes before historic /l/
• Scottish vowel length rule
• Phonological history of Scots

References

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Notes and References

1. https://wordhistories.net/2017/06/02/origin-of-sneeze/ word histories: sneeze
2. E. J. Dobson (English pronunciation, 1500–1700, Oxford: Clarendon Press, 1968, passim) and other scholars before him postulated the existence of a vowel /y/ beside /iu̯/ in early Modern English. But see Fausto Cercignani, On the alleged existence of a vowel /y:/ in early Modern English, in “English Language and Linguistics”, 26/2, 2022, pp. 263–277 https://www.cambridge.org/core/journals/english-language-and-linguistics/article/on-the-alleged-existence-of-a-vowel-y-in-early-modern-english/AC739707E998A98AFFD515678D9B1E14
3. Web site: Grama . James . Travis . Catherine E . González . Simón . Initiation, progression, and conditioning of the short-front vowel shift in Australia . Academia . January 2019 . 4 December 2023.
4. Web site: Morgen – a suitable case for treatment. Lindsey. Geoff. 2012-07-15.
5. Book: Beal, Joan . A Handbook of Varieties of English Volume 1: Phonology. Bernd Kortmann and Edgar W. Schneider . De Gruyter. 2004. 123–124.
6. Book: Stuart-Smith, Jane . A Handbook of Varieties of English Volume 1: Phonology. Bernd Kortmann and Edgar W. Schneider . De Gruyter. 2004. 54.
7. Web site: 2006-05-12 . Annexe 4: Linguistic Variables . 2024-02-20 . https://web.archive.org/web/20060512015006/http://www.arts.gla.ac.uk/SESLl/EngLang/research/accent/annex4.htm . 2006-05-12 .
8. Reversal and re-organization of the Northern Cities Shift in Michigan . S. E. . Wagner . A. . Mason . M. . Nesbitt . E. . Pevan . M. . Savage . 2016 . University of Pennsylvania Working Papers in Linguistics 22.2: Selected Papers from NWAV 44 . 2018-07-14 . 2021-06-23 . https://web.archive.org/web/20210623223821/http://msusociolinguistics.weebly.com/uploads/9/3/1/9/9319621/reversalandreorganization_nwav44.pdf . dead .
9. Reversal of the Northern Cities Shift in Syracuse, New York . Anna . Driscoll . Emma . Lape . University of Pennsylvania Working Papers in Linguistics . 21 . 2 . 2015.
10. Dinkin, Aaron (2017). "Escaping the TRAP: Losing the Northern Cities Shift in Real Time (with Anja Thiel)". Talk presented at NWAV 46, Madison, Wisc., November 2017.
11. Web site: The British English vowel system. 2012-03-08. Lindsey. Geoff. 2024-11-09.