"The House of Habsburg (pron.: /hæps.br/; German pronunciation: [ha?ps.bk]), also Hapsburg, and also known as House of Austria is one of the most important royal houses of Europe and is best known for being an origin of all of the formally elected Holy Roman Emperors between 1438 and 1740, as well as rulers of the Austrian Empire and Spanish Empire and several other countries. The House takes its name from Habsburg Castle, a fortress built around 1020?1030 in present day Switzerland by Count Radbot of Klettgau, who chose to name his fortress Habsburg. His grandson, Otto II, was the first to take the fortress name as his own, adding "von Habsburg" to his title."--Wikipedia.