The Kingdom of Hungary was a multiethnic state from its inception until the Treaty of Trianon and it covered what is today Hungary, Slovakia, Transylvania and other parts of Romania, Carpathian Ruthenia (now part of Ukraine), Vojvodina (now part of Serbia), the territory of Burgenland (now part of Austria), Međimurje (now part of Croatia), Prekmurje (now part of Slovenia) and a few villages in which are now part of Poland. From 1102 it also included the Kingdom of Croatia, being in personal union with it, united under the King of Hungary.