According to the Treaty of Trianon, the city of Sopron in western Hungary and its surroundings were assigned to Austria. After an uprising in 1921 in this region, a referendum was held and 65.8% of the votes were in favor of belonging to Hungary. This referendum was accepted by the major powers and the transition of Sopron and its surrounding 8 villages from Austria to Hungary was the only serious territorial revision in the years following the Treaty of Trianon.