Northern Transylvania (, ) was the region of the Kingdom of Romania that during World War II, as a consequence of the August 1940 territorial agreement known as the Second Vienna Award, became part of the Kingdom of Hungary. With an area of , the population was largely composed of both ethnic Romanians and Hungarians. In October 1944, Soviet and Romanian forces gained control of the territory, and by March 1945 Northern Transylvania returned to Romanian administration. After the war, this was confirmed by the Paris Peace Treaties of 1947. Background The region has a varied history. It was once the nucleus of the Kingdom of Dacia (82 BC–106 AD). In 106 AD the Roman Empire conquered the territory, systematically exploiting its resources. After the Roman legions 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. During the 9th century, Bulgarians ruled Transylvania. The Magyars conquered much of Central Europe at the end of the 9th century and for almost six hundred years, Transylvania was a voivodeship in the Kingdom of Hungary. After the Battle of Mohács in 1526 and the Hungarian defeat by the Ottomans, Transylvania became a semi-independent principality (the Principality of Transylvania) under local Hungarian nobility rule, but owing suzerainty to the Ottoman Empire. It then became a province (Principality/Grand Principality of Transylvania) of the Habsburg monarchy/Austrian Empire as a Land of the Hungarian Crown, and after 1848, and again from 1867 to 1918 it was incorporated into the Kingdom of Hungary within the Austro-Hungarian Empire. The dual monarchy dissolved after World War I. The ethnic Romanians, who formed the majority population of Transylvania, elected representatives who proclaimed the Union with Romania on 1 December 1918. The Proclamation of Union at Alba Iulia was adopted by the Deputies of the Romanians from Transylvania during the Great National Assembly of Alba Iulia, supported one month later by the vote of the Deputies of the Transylvanian Saxons during the Mediaș Assembly. By Spring 1919, during the Hungarian–Romanian War, Transylvania came under administrative control of Romania. Eventually in June 1920 the Treaty of Trianon assigned Transylvania to the Kingdom of Romania. The text of the Second Vienna Award The final route of the border line, which separates Romania from Hungary, will correspond to the one marked on the geographical map attached here.