The House of Habsburg (; German: Haus Habsburg, lit. 'House of the Hawk's hill' [haʊs ˈhaːbsbʊrɡ] ), also known as the House of Austria, was one of the most powerful dynasties in the history of Europe and Western civilization. They were best known for ruling vast realms throughout Europe and the Americas during the Middle Ages and early modern period, including the Holy Roman Empire and Spain.
The house takes its name from Habsburg Castle, a fortress built in the 1020s in present-day Switzerland by Radbot of Klettgau, who named his fortress Habsburg. His grandson Otto II was the first to take the fortress name as his own, adding "Count of Habsburg" to his title. In 1273, Count Radbot's seventh-generation descendant, Rudolph, was elected King of the Romans. Taking advantage of the extinction of the Babenbergs and of his victory over Ottokar II of Bohemia at the Battle on the Marchfeld in 1278, he appointed his sons as Dukes of Austria and moved the family's power base to Vienna, where the Habsburg dynasty gained the name of "House of Austria" and ruled until 1918.
