Ulrich III (c. 1220 – 27 October 1269) was the Lord in the March of Carniola from c. 1249 and Duke of Carinthia from 1256 until his death, the last ruler from the House of Sponheim. His rule had long-lasting consequences. In Carniola, he acquired the former Meranian possessions, thus becoming the first undisputed princeps terrae, provincial lord or landgrave, creating the power and legal basis of the future Duchy of Carniola. The center of his original Carniolan possessions, Ljubljana, became the new administrative center and thus the provincial capital, as well as the center of Ulrich's power. In Carinthia, which he took over after his father's death, his seal became the coat of arms of Carinthia up to today. Despite his attempts to secure the vast Babenberg inheritance through two marria