In 1269, Ottokar also effectively controlled the Duchy of Carinthia, with Carniola and the Windic March further in the south. He controlled, in all, a Central European realm stretching from the Polish border in the Sudetes towards the Adriatic coast in the south. When he failed to be elected King of the Romans in 1273, he contested the election of the successful candidate, the Swabian count Rudolf of Habsburg. Nevertheless, Rudolf was able to secure his rule as the first actual German king after the Great Interregnum. By his Imperial authority he seized Ottokar's alienated territories and added them to his already extensive homelands in Swabia. King Ottokar was finally defeated and killed by the united Austrian and Hungarian forces in the 1278 Battle on the Marchfeld.