empire alone, the vast possessions included the original hereditary lands, the Erblande, from before 1526; the lands of the Bohemian crown; the formerly Spanish Netherlands from 1714 until 1794; and some fiefs in Imperial Italy. Outside the empire, they encompassed all the lands of the crown of Hungary as well as conquests made at the expense of the Ottoman Empire. The dynastic capital was Vienna, except from 1583 to 1611, when it was in Prague. Origins and expansion The first Habsburg who can be reliably traced was Radbot of Klettgau, who was born in the late 10th century; the family name originated with Habsburg Castle, in present-day Switzerland, which was built by Radbot. After 1279, the Habsburgs came to rule in the Duchy of Austria, which was part of the elective Kingdom of Germany within the Holy Roman Empire. King Rudolf I of Germany of the Habsburg family assigned the Duchy of Austria to his sons at the Diet of Augsburg (1282), thus establishing the "Austrian hereditary lands". From that moment, the Habsburg dynasty was also known as the House of Austria. Between 1438 and 1806, with few exceptions, the Habsburg Archduke of Austria was elected as Holy Roman Emperor. The Habsburgs grew to European prominence as a result of the dynastic policy pursued by Maximilian I, Holy Roman Emperor. Maximilian married Mary of Burgundy, thus bringing the Burgundian Netherlands into the Habsburg possessions. Their son, Philip the Handsome, married Joanna the Mad of Spain (daughter of Ferdinand II of Aragon and Isabella of Castile). Charles V, Holy Roman Emperor, the son of Philip and Joanna, inherited the Habsburg Netherlands in 1506, Habsburg Spain and its territories in 1516, and Habsburg Austria in 1519. At this point, the Habsburg possessions were so vast that Charles V was constantly travelling throughout his dominions and therefore needed deputies and regents, such as Isabella of Portugal in Spain and Margaret of Austria in the Low Countries, to govern his various realms. At the Diet of Worms in 1521, Emperor Charles V came to terms with his younger brother Ferdinand. According to the Habsburg compact of Worms (1521), confirmed a year later in Brussels, Ferdinand was made Archduke, as a regent of Charles V in the Austrian hereditary lands. Following the death of Louis II of Hungary in the Battle of Mohács against the Ottoman Turks, Archduke Ferdinand (who was his brother-in-law by virtue