Ernest the Iron was Duke of Styria, Carinthia and Carniola from 1406 until his death. He was a member of the Habsburg dynasty, of the Leopoldian line, whose head of the family he was from 1411 to 1424.
Ernest was born in Bruck an der Mur, Styria, the third son of Leopold III, Duke of Inner Austria. After the death of his father in the Battle of Sempach in 1386, he stood under the guardianship of Albert III. In 1401 he accompanied the German King Rupert on his campaign in Italy. Upon the death of their eldest brother William, Duke of Inner Austria in 1406, the remaining three brothers agreed about the future partition of their patrimony. In the separation agreement of 1406, Ernest received Styria, Carinthia and Carniola, and jointly with his elder brother duke Leopold IV , held the guardianship over young Albert V, Duke of Austria. In 1407, conflicts between Leopold and Ernest resulted in a civil war that lasted until May 1409. When Leopold died without a male heir in 1411, Ernest became the uncontested head of the Leopoldian family. In 1414, he became the last Duke to be enthroned according to the traditional rite in Carinthia, and from that time on called himself Archduke. He was th
Source: Wikipedia