The term Vlachs (Croatian: Vlasi) was initially used in medieval Croatian and Venetian history for a Romance-speaking pastoralist community, called "Vlachs" and "Morlachs", inhabiting the mountains and lands of the Croatian Kingdom and the Republic of Venice (Venetian Dalmatia) from the early 14th century. By the end of the 15th century they were highly assimilated with the Slavs and lost their language or were at least bilingual, while some communities managed to preserve and continue to speak their language (Istro-Romanians).
Later in the 16th and 17th century with the Ottoman conquest and mass migrations, the term was primarily used for a socio-cultural and professional segment of the population rather than to an ethnicity, and referred to the mostly Slavic-speaking emigrants and refugees from Ottoman-held territories to the Habsburg Empire (such as Croatia) and the Republic of Venice (Dalmatia), mostly of Eastern Orthodox faith, and to a lesser degree, Catholic. With the nation-building in the 19th century this population played a significant part in the national ideologies in Croatia and Serbia,[1] and according to religious confession espoused either Croat or Serb ethnicity.
In Croatia today, the Vlachs are a recognized national minority (along with 22 other ethnic groups), with 29 individuals declared as Vlachs in the 2011 Croatian census, making them the smallest recognized minority in Croatia. Other ethnic groups that were also traditionally referred to as Vlachs in Croatia now identify by their respective ethnic names – namely Serbs, Romanians, Aromanians and Istro-Romanians (which are native to modern Croatia's Istria County).