In 1278, not as yet eight years old, he was promised in marriage to Agnes of Bohemia which took place in March 1289. Beforehand, in 1282, he was promoted to the Reichsfuerstenstand and received Schwaben and Austria. Rudolf's father tried to have him elected as his successor as
well as promising that within four years he would receive a Duchy, a kingdom or a large amount of money. He was described as physically strong and warrior-like but most of his time was spent on the administration of his territories. In 1290 he visited his sister Guta in Prague and died suddenly. As a result he never received what had been promised him.
 

Source: Leo van de Pas