House of Habsburg
The House of Habsburg (//), alternatively spelled Hapsburg in English and also known as the House of Austria is one of the most prominent and important dynasties in European history.
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 of Habsburg 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.
The throne of the Holy Roman Empire was continuously occupied by the Habsburgs from 1440 until their extinction in the male line in 1740 and, after the death of Francis I, from 1765 until its dissolution in 1806. The house also produced kings of Bohemia, Hungary, Croatia, Spain, Portugal and Galicia-Lodomeria, with their respective colonies; rulers of several principalities in the Low Countries and Italy; and in the 19th century, emperors of Austria and of Austria-Hungary as well as one emperor of Mexico. The family split several times into parallel branches, most consequentially in the mid-16th century between its Spanish and Austrian branches following the abdication of Charles V. Although they ruled distinct territories, the different branches nevertheless maintained close relations and frequently intermarried.