Transylvania backed by the mobilization of Romanian troops, proclaimed Union with Romania on 1 December 1918. The "Proclamation of Union" of Alba Iulia was adopted by the Deputies of the Romanians from Transylvania, and supported one month later by the vote of the Deputies of the Saxons from Transylvania. The national holiday of Romania, the Great Union Day (also called "Unification Day") occurring on December 1, celebrates this event. The holiday was established after the Romanian Revolution, and marks the unification not only of Transylvania, but also of the provinces of Banat, Bessarabia and Bukovina with the Romanian Kingdom. These other
Transylvania withdrew in 271 AD, it was overrun by a succession of various tribes, bringing it under the control of the Carpi, Visigoths, Huns, Gepids, Avars and Slavs. From 9th to 11th century Bulgarians ruled Transylvania. It is a subject of dispute whether elements of the mixed Daco–Roman population survived in Transylvania through the Post-classical Era (becoming the ancestors of modern Romanians) or the first Vlachs/Romanians appeared in the area in the 13th century after a northward migration from the Balkan Peninsula. There is an ongoing scholarly debate over the ethnicity of Transylvania's population before the Hungarian conquest (see Origin of