Vlach is a blanket term covering several modern Latin peoples descending from the Latinized population in Central, Eastern and Southeastern Europe.

English variations on the name include: Wallachians, Walla, Wlachs, Wallachs, Vlahs, Olahs or Ulahs.

Groups that have historically been called Vlachs include: modern-day Romanians or Daco-Romanians, Aromanians or Macedo-Romanians, Morlachs, Megleno-Romanians and Istro-Romanians.

Since the creation of the Romanian state, the term in English has mostly been used for those living outside Romania.The Vlachs, which would develop into the modern Romanian ethnicity, do not become tangible before the High Middle Ages in Kedrenos (11th century), and their prehistory during the Migration period is a matter of scholarly speculation[ but according to the linguists and to many scholars, the existence of the present Eastern Romance languages prove the survival of the Thraco-Romans in the low-Danube basin during the Migration period and the Vlachs are all being well considered descendants of Romanized peoples of the area (incl.

Thracians, Dacians and Illyrians).

The term Vlach is originally an exonym.

All the Vlach groups used various words derived from romanus to refer to themselves: Români, Rumâni, Rumâri, Aromâni, Arumâni etc.

(Note: the Megleno-Romanians nowadays call themselves "Vlaşi"; the Istro-Romanians also have adopted the names Vlaşi, but still use Rumâni and Rumâri to refer to themselves).The Vlach languages, also called the Eastern Romance languages, have a common origin from the Proto-Romanian language.

Over the centuries, the Vlachs split into various Vlach groups and mix with neighboring populations: South Slavs, Greeks, Albanians, Bulgars, and others.Almost all modern nations in Central and Southeastern Europe have native Vlach minorities: Hungary, Ukraine, Serbia, Croatia, Macedonia, Albania, Greece and Bulgaria.

In other countries, the native Vlach population have been completely assimilated by the Slavic population and therefore ceased to exist: Poland, Czech Republic, Slovakia, Bosnia and Montenegro.

Only in Romania and the Republic of Moldova does the Vlach (Daco-Romanian or Romanian proper) population comprise an ethnic majority today.