Monoethnicity is the existence of a single ethnic group in a given region or country. It is the opposite of polyethnicity.
An example of a largely monoethnic country is Japan. It is a common belief in Japan that the entire country is monoethnic, but a few ethnic minorities live in Japan (e.g. Koreans, Ainus, and Ryukyuans). They represent around 1% of the whole population.[1]
South Korea is another monoethnic country. There are small ethnic minorities that exist in South Korea, where they account for around 1% of the South Korean population. These include around 650,000 Chinese immigrants.
Most African countries have what would be considered a mono-racial society, but it is common to find dozens of ethnic groups within the same country.
The Yugoslav Wars are noted as having made Yugoslavia's successor states "de facto and de jure monoethnic nation-states", with Bosnia and Herzegovina further diving itself into mono-ethnic enclaves.[2]
Because not all countries collect data on ethnicity, and the collection of data usually relies on self-reporting, it can be difficult to discern how monoethnic a country is.
Sovereign states
| Rank | Country | Population | Dominant group | % | Notes | |
|---|---|---|---|---|---|---|
| 1 |  Egypt | 111,247,248 | Egyptian | 99.7% | ||
| 2 |  Lesotho | 2,227,548 | Basotho | 99.7% | ||
| 3 |  Algeria | 47,022,473 | Arab-Amazigh | 99% | Although almost all Algerians are Amazigh in origin and not Arab, only a minority identify themselves as primarily Amazigh | |
| 4 |  Bangladesh | 168,697,184 | Bengali | 99% | ||
| 5 |  Morocco | 37,387,585 | Arab-Amazigh | 99% | Does not include data from Western Sahara | |
| 6 |  Vanuatu | 318,007 | Ni-Vanuatu | 99% | ||
| 7 |  Armenia | 2,976,765 | Armenian | 98.1% | ||
| 8 |  Tunisia | 12,048,847 | Arab | 98% | ||
| 9 |  Albania | 3,107,100 | Albanian | 98% | ||
| 10 |  Japan | 123,201,945 | Japanese | 97.5% | ||
| 11 |  Poland | 38,746,310 | Polish | 96.9% | This number represents the percentage of people who indicated Polish as their primary ethnicity | |
| 12 |  Tonga | 104,889 | Tongan | 96.5% | ||
| 13 |  Kiribati | 116,545 | I-Kiribati | 95.78% | ||
| 14 |  Marshall Islands | 82,011 | Marshallese | 95.6% | ||
| 15 |  Cambodia | 17,063,669 | Khmer | 95.4% | ||
| 16 |  Solomon Islands | 726,799 | Melanesian | 95.4% | ||
| 17 |  Lebanon | 5,364,482 | Arab | 95% | ||
| 18 |  Portugal | 10,207,177 | Portuguese | 95% | ||
| 19 |  Nauru | 9,892 | Nauruan | 94.6% | ||
| 20 |  Azerbaijan | 10,650,239 | Azerbaijani | 91.6% | ||
| 21 |  Croatia | 4,150,116 | Croatian | 91.6% | ||
| 22 |  China | 1,416,043,270 | Han Chinese | 91.1% | ||
| 23 |  Saudi Arabia | 36,544,431 | Arab | 90% | ||
| 24 |  Romania | 18,148,155 | Romanian | 89.3% | Data represents only those who declared an ethnicity in the 2021 census | |
| 25 |  Turkmenistan | 5,744,151 | Turkmen | 87.6% | ||
| 26 |  Georgia | 4,900,961 | Georgian | 86.8% | ||
| 27 | 105,758,975 | Viet | 85.3% | |||
| Country | Population | Dominant group | % | ||
|---|---|---|---|---|---|
| 5,483,450 | Palestinian Arab | 91% | |||
| 265,100 | Turkish Cypriots | 99.2% | |||
| 3,500,000 | Somalis | 99% | |||
| 23,347,374 | Han Chinese | 97% | [3] [4] | ||
 Hong Kong | 7,249,907 | Cantonese people and Taishanese people | 92% | ||
| 1,586,659 | Albanians | 92% | [5] | ||
 Greenland | 55,877 | Inuit | 89.7% | ||
| 53,532 | Ossetians | 89.9% | |||
| 614,458 | Cantonese people and Macanese people | 88.7% | |||
| 30,696 | Ålanders | 86.5% |