Ernest was made a member of the Order of the Dragon and of the Equestrian Order of the Holy Sepulchre of Jerusalem in 1414, however, he became bitter with the Luxembourg king Sigismund from 1412 onwards. When his brother Frederick IV, a supporter of Antipope John XXIII at the Council of Constance, was banned by the king in 1417, Ernest first attempted to gain control over Frederick's territories himself, but then came to an agreement with him and successfully defended Tyrol against Sigismund's pretensions. Ernest turned out to be a capable ruler of the Inner Austrian lands; his eldest son Frederick V would become sole heir of all Habsburg lines, elected King of the Romans in 1440 and crowned Holy Roman Emperor in 1452.