The Romanized Thracian ( Thraco - Roman ) and Illyrian inhabitants of those regions retained the Roman name ( Romanians ) and the Latin tongue .
Those regions came to be known as Vlachs by foreigners in the Middle Ages .
The Romanized Thracian ( Thraco - Roman ) and Illyrian inhabitants of those regions , who came to be known as Vlachs by foreigners in the Middle Ages , retained the Roman name ( Romanians ) and the Latin tongue .