The House of Esterházy (also spelled Eszterházy, ) is a Hungarian noble family beginning in the Middle Ages. Since the 17th century they were among the great landowner magnates of the Kingdom of Hungary, during the time it was part of the Habsburg Empire and later Austria-Hungary. During the history of the Habsburg empire, the Esterházys were consistently loyal to the Habsburg rulers. They received the title of count in 1626 and the Forchtenstein line received the title of Fürst (Ruling Prince) by the Holy Roman Emperor in 1712.