Editing History of Austria (section)

==== Rudolph I and primogeniture (1278–1358) ====
[[Rudolf I of Germany|Rudolf I]] spent several years establishing his authority in Austria, finding some difficulty in establishing his family as successors to the rule of the province. At length the hostility of the princes was overcome and he was able to bequeath Austria to his two sons. In December 1282, at the Diet of [[Augsburg]], Rudolph invested the duchies of Austria and Styria on his sons, [[Albert I of Germany|Albert I]] (1282–1308) and [[Rudolph II, Duke of Austria|Rudolph II the Debonair]] (1282–1283) as co-rulers "jointly and severally", and so laid the foundation of the House of Habsburg. Rudolf continued his campaigns subduing and subjugating and adding to his domains, dying in 1291, but leaving dynastic instability in Austria, where frequently the Duchy of Austria was shared between family members. However Rudolf was unsuccessful in ensuring the succession to the imperial throne for the Dukes of Austria and Styria.

The conjoint dukedom lasted only a year until the [[Treaty of Rheinfelden]] in 1283 established the Habsburg [[order of succession]]. Establishing primogeniture, then eleven-year-old Duke Rudolph II had to waive all his rights to the thrones of Austria and Styria to the benefit of his elder brother Albert I. While Rudolph was supposed to be compensated, this did not happen, dying in 1290, and his son [[John Parricida|John]] subsequently murdered his uncle Albert I in 1308. For a brief period, Albert I also shared the duchies with [[Rudolf I of Bohemia|Rudolph III]] the Good (1298–1307), and finally achieved the imperial throne in 1298.

On Albert I's death, the duchy but not the empire passed to his son, [[Frederick the Fair]] (1308–1330), at least not until 1314 when he became co-ruler of the empire with [[Louis IV, Holy Roman Emperor|Louis IV]]. Frederick also had to share the duchy with his brother [[Leopold I, Duke of Austria|Leopold I]] the Glorious (1308–1326). Yet another brother, [[Albert II, Duke of Austria|Albert II]] the Lame (1330–1358) succeeded Frederick.

The pattern of corule persisted, since Albert had to share the role with another younger brother [[Otto, Duke of Austria|Otto I]] the Merry (1330–1339), although he did attempt to unsuccessfully lay down the rules of succession in the "Albertinian House Rule". When Otto died in 1339, his two sons, Frederick II and Leopold II replaced him, making three simultaneous Dukes of Austria from 1339 to 1344 when both of them died in their teens without issue. Single rule in the Duchy of Austria finally returned when his son, Rudolph IV succeeded him in 1358.

In the 14th century the Habsburgs began to accumulate other provinces in the vicinity of the Duchy of Austria, which had remained a small territory along the Danube, and Styria, which they had acquired with Austria from Ottokar. In 1335 Albert II inherited the [[Duchy of Carinthia]] and the [[March of Carniola]] from the then rulers, the [[House of Gorizia]].