The Thirty Tyrants (Latin: Tyranni Triginta) were a series of thirty rulers who appear in the Historia Augusta, as having ostensibly been pretenders to the throne of the Roman Empire during the reign of the emperor Gallienus.
Given the notorious unreliability of the Historia Augusta, the veracity of this list is debatable. There is a scholarly consensus that the author deliberately inflated the number of pretenders in order to parallel the Thirty Tyrants of Athens.
The Historia actually gives 32 names. The author, who wrote under the name of Trebellius Pollio, places the last two during the reigns of Maximinus Thrax and Claudius II respectively, leaving thirty alleged pretenders during the reign of Gallienus.
The following list gives the Thirty Tyrants as depicted by the Historia Augusta, along with notes contrasting the Historia Augusta's claims with their actual historical positions:
| Chapter in Historia Augusta | Name | Notes about historicity | |
|---|---|---|---|
| 2 | Cyriades | never claimed Imperial dignity | |
| 3 | Postumus | accurate placement | |
| 4 | Postumus Junior | youth; probably never existed[1] | |
| 5 | Laelianus | accurate placement | |
| 6 | Victorinus | contemporary not with Gallienus but Claudius II and Aurelian | |
| 7 | Victorinus Junior | Fiction, never existed[2] | |
| 8 | Marius | accurate placement | |
| 9 | Ingenuus | accurate placement | |
| 10 | Regalianus | accurate placement | |
| 11 | Aureolus | accurate placement | |
| 12 | Macrianus | accurate placement | |
| 13 | Macrianus Junior | accurate placement | |
| 14 | Quietus | accurate placement | |
| 15 | Odaenathus | never claimed Imperial dignity | |
| 16 | Herodes | youth, never claimed Imperial dignity, but older brother of Vaballathus (see below), who did so. | |
| 17 | Maeonius | never claimed Imperial dignity | |
| 18 | Balista | never claimed Imperial dignity | |
| 19 | Valens | probably never claimed Imperial dignity | |
| 20 | Valens Superior | contemporary of Decius, not Valerianus | |
| 21 | Piso | probably never claimed Imperial dignity | |
| 22 | Aemilianus | probably never claimed Imperial dignity | |
| 23 | Saturninus | probably fictitious | |
| 24 | Tetricus Senior | contemporary not with Gallienus but Claudius II and Aurelian | |
| 25 | Tetricus Junior | youth, contemporary not with Gallienus but Claudius II and Aurelian | |
| 26 | Trebellianus | probably fictitious | |
| 27 | Herennianus | youth, never claimed Imperial dignity, possibly fictitious | |
| 28 | Timolaus | youth, never claimed Imperial dignity, possibly fictitious | |
| 29 | Celsus | probably fictitious | |
| 30 | Zenobia | female, accurate placement, her son Vaballathus also claimed imperial dignity | |
| 31 | Victoria (or Vitruvia) | female, never claimed Imperial dignity | |
| 32 | Titus | admittedly not contemporary with Gallienus but Maximinus Thrax | |
| 33 | Censorinus | admittedly not contemporary with Gallienus but Claudius II |
Notwithstanding the author's pretensions regarding the time during which these persons aspired to the throne, this list includes:
Leaving nine pretenders roughly contemporary with Gallienus. According to David Magie (the editor of the Loeb Classical Library edition of the Historia Augusta), at least some of these men issued coins.