The family, which can be traced to the 10th cent., originally held lands in Alsace and in NW Switzerland. Otto (d. 1111) took the name Hapsburg from a castle near Aargau, Switzerland, when he was designated count. Vast estates in Upper Alsace, Baden, and Switzerland were inherited (1173) by his grandson Count Albert III (d. 1199) and passed to Rudolf II (d. 1232) and Albert IV (d. c.1240). The extinction of the houses of Lenzburg, Zähringen, and Kyburg facilitated family acquisitions.
The election (1273) of Count Rudolf IV as Rudolf I, king of the Germans, provoked war with King Ottocar II of Bohemia. Ottocar's defeat and death at the Marchfeld (1278) confirmed Hapsburg possession of Austria, Carniola, and Styria; these lands and the Austrian ducal title were declared hereditary by Rudolf in 1282. In 1335 Carinthia too was claimed. Possession of these dominions marked the rise of the Hapsburgs to European significance. Held in common by the sons of Albert I and of Albert II, the many lands were divided, after the death (1365) of Duke Rudolf IV, between the Albertine and Leopoldine lines (named for his brothers).
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.