He was the second son of Leopold III. His eldest brother Duke William of Inner Austria took him as his effective co-ruler, putting him in particular charge of Further Austria, which also meant ancestral Habsburg lands in Swiss Aargau etc. Leopold was to face Swiss opposition to Austrian administration.
From 1391 onwards, he was the effective ruler of Further Austria, and from 1396 to 1406 he was ruler in Tyrol too.
His younger brothers Ernest the Iron and Frederick were, for the time being, left to grow up. They were initiated with ducal positions in 1402. In 1406 their eldest brother Duke William died without leaving heirs, and Leopold became the next head of their family. Leopold had no sons either. The younger brothers made an agreement how to divide the patrimony in the future: Ernest was to receive Inner Austria and Frederick Further Austria, including Tyrol. Ernest took the reins in Styria, etc. Frederick was only barely in his twenties, but was put in charge in Tyrol. Leopold was left with responsibility of the Further Austrian territories, together with the position of head of the family.
In 1406, Leopold took over the guardianship of their young cousin Albert V, which resulted in conflicts with his brother Ernest.
