In 1268 Ottokar signed a contract of inheritance with Ulrich III and thus acquired Carinthia including the March of Carniola and the Windic March one year later .
Ulrich III is the last Carinthian duke of the House of Sponheim .
In 1268 Ottokar signed a contract of inheritance with Ulrich III , the last Carinthian duke of the House of Sponheim , and thus acquired Carinthia including the March of Carniola and the Windic March one year later .