Frederick IV, Duke of Austria

Frederick IV, Duke of Further Austria (1382 – 24 June 1439), also known as Frederick of the Empty Pockets, was the Habsburg duke of Further Austria from 1402, and Count of Tyrol from 1406, until his death. He was the younger son of Leopold III, Duke of Inner Austria.
Frederick's rule over Tyrol and the scattered Habsburg territories in southwestern Germany and in the Alsace referred to collectively as Vorderösterreich (Further Austria) was formalized in 1402 through a partition of his father's inheritance. Later, in 1406, his elder brother Leopold IV ceded Tyrol to his sole rule when their eldest brother William died; and Frederick became sole ruler in Further Austria only upon Leopold's death in 1411. The early years of Frederick's reign were marked by external and internal conflicts. He had to overcome the opposition of the local nobles (who gave him the title of "Empty Pockets") in 1406/07, and had to deal with the independence movement in Appenzell, which became a protectorate of the Old Swiss Confederacy in 1411.
When he sided with Antipope John XXIII at the Council of Constance, Emperor Sigismund placed him under the Imperial ban. Thanks to the support of the local populace he managed to keep Tyrol, but he lost the Aargau, the old homeland of the Habsburgs, to the Swiss.
By 1425, his rule over Tyrol had stabilized, partially due to the successful beginning of silver mining that brought an increase in prosperity to the region.
Frederick also moved the court from Meran to Innsbruck.
On 24 December 1407, Frederick married Elisabeth of the Palatinate (1381–1408), daughter of Rupert, King of the Romans in Innsbruck, but she died the following year.
On 11 June 1411, Frederick married Anna, daughter of Frederick I, Duke of Brunswick-Lüneburg; they had one son, Sigismund.

• By Elisabeth of the Palatine:
  • Elisabeth (27 – 28 December 1408)
• By Anna of Brunswick-Lüneburg:
  • Margaret (1423 – 6 July 1424)
  • Hedwig (1424 – 21 February 1427)
  • Wolfgang (26 February 1426)
  • Sigismund (26 October 1427 – 4 March 1496)