Transylvania modern Romania. The plateau is almost entirely surrounded by the Eastern, Southern and Romanian Western branches of the Carpathian Mountains. The area includes the Transylvanian Plain. Other areas to the west and north are widely considered part of Transylvania. In common reference, the Western border of Transylvania has come to be identified with the present Romanian-Hungarian border, settled in the 1920 Treaty of Trianon, though geographically the two are not identical. Ethnographic areas: The area of the historical Voivodeship is . The regions granted to Romania in 1920 covered 23 counties including nearly (102,787–103,093 km in Hungarian sources and 102,200
Principality of Transylvania (1570–1711) West and north Royal Hungary, Ottoman Hungary, and the Eastern Hungarian Kingdom under Ottoman suzerainty, which later became the Principality of Transylvania where Austrian and Turkish influences vied for supremacy for nearly two centuries. The Hungarian magnates of Transylvania resorted to policy of duplicity in order to preserve independence. Transylvania was administrated by Isabella, John Sigismund's mother from 1541 to 1551, when it fell for 5 years (1551–1556) under Habsburg rule. The House of Zapolya gained again the control of Transylvania in 1556, when the Diet of Szászsebes elected Sigismund as prince of Transylvania. Transylvania was now beyond the reach