Charles I of Austria or Charles IV of Hungary (Karl Franz Joseph Ludwig Hubert Georg Otto Marie; 17 August 1887 – 1 April 1922) was, among other titles, the last ruler of the Austro-Hungarian Empire. He was the last Emperor of Austria, the last King of Hungary, the last King of Bohemia and Croatia and the last King of Galicia and Lodomeria and the last monarch of the House of Habsburg-Lorraine.