By the second half of the 13th century, count Rudolph IV (1218–1291) had become an influential territorial lord in the area between the Vosges Mountains and Lake Constance. On , he was elected as a compromise candidate as King of the Romans and received the name Rudolph I of Germany. He then led a coalition against king Ottokar II of Bohemia who had taken advantage of the Great Interregnum in order to expand southwards, taking over the respective inheritances of the Babenberg (Austria, Styria, Savinja) and of the Spanheim (Carinthia and Carniola). In 1278, Rudolph and his allies defeated and killed Ottokar at the Battle of Marchfeld, and the lands he had acquired reverted to the German crown. With the Georgenberg Pact of 1286, Rudolph secured for his family the duchies of Austria and Styria. The southern portions of Ottokar's former realm, Carinthia, Carniola, and Savinja, went to Rudolph's allies from the House of Gorizia.