There are several well-supported theories about the
origin of the Romanians. It is without doubt that the
Romanian language is descended from the
Vulgar Latin dialects spoken in the
Roman provinces north of the "
Jirecek Line" (a proposed notional line separating the predominantly
Latin-speaking territories from the
Greek-speaking lands in
Southeastern Europe) in
Late Antiquity. The theory of Daco-Roman continuity argues that the
Romanians are mainly descended from the
Daco-Romans, a people developing through the cohabitation of the native
Dacians and the Roman colonists in the province of
Dacia Traiana (primarily in present-day
Romania) north of the river
Danube. The competing immigrationist theory states that the Romanians' ethnogenesis commenced in the provinces south of the river with Romanized local populations (known as
Vlachs in the Middle Ages) spreading through mountain refuges, both south to
Greece and north through the
Carpathian Mountains. According to the "admigration theory", migrations from the
Balkan Peninsula to the lands north of the Danube contributed to the survival of a Romance-speaking population in those territories.