Charles I of Austria
Charles I or Karl I (Karl Franz Joseph Ludwig Hubert Georg Otto Maria; 17 August 18871 April 1922) was the last Emperor of Austria, the last King of Hungary (as Charles IV, ), the last King of Bohemia (as Charles III), and the last monarch belonging to the House of Habsburg-Lorraine. After his uncle Archduke Franz Ferdinand of Austria was assassinated in 1914, Charles became heir presumptive of Emperor Franz Josef. Charles I reigned from 1916 until 1918, when he "renounced participation" in state affairs, but did not abdicate. He spent the remaining years of his life attempting to restore the monarchy until his death in 1922. Beatified by Pope John Paul II in 2004, he is known to the Catholic Church as Blessed Karl of Austria.
Ottokar II of Bohemia
Father and son were eventually reconciled to assist the king's aim of acquiring the neighbouring Duchy of Austria, where the last Babenberg duke Frederick II had been killed in the 1246 Battle of the Leitha River. King Wenceslaus had initially attempted to acquire Austria by marrying his heir, Vladislav, to the last duke's niece Gertrude of Babenberg. That match had been cut short by Vladislav's death and Gertrude's remarriage to the Zähringen margrave Herman VI of Baden. The latter was rejected by the Austrian nobility and could not establish his rule. Wenceslaus used this as pretext to invade Austria when Herman died in 1250 — according to some sources, the estates called upon him to restore order.