It was now necessary to get a formal sanction for these conquests; and Ottakar chose Richard of Cornwall, from the rival claimants to the German Empire, as the puppet most useful for this purpose. Richard was willing enough to secure so influential a supporter; but the King of Hungary was not so easily satisfied. In 1260, he once more poured his forces into Styria and Austria; and he was now followed, not only by the Hungarian troops, but by the savage Cumanians, and even, according to one account, by the Tartars. The struggle was a fierce one; but it ended in the complete victory of the Bohemians.
Ottakar, however, thought it necessary to secure himself against future invasions, by a singularly questionable step. The unfortunate Margaret, to whom, it was evident, he must very soon have become unfaithful, was to be repudiated on the ground of her former vow of virginity, in order that Ottakar might marry Kunigunda, the daughter of Bela, King of Hungary. Urban IV., like many of his predecessors, was extremely desirous to procure a good understanding between Hungary and Bohemia, as in the union of these kingdoms he saw the best hope of security against a future Tartar invasion; so Kunigunda was crowned Queen of Bohemia by the Archbishop of Mainz.
But Ottakar’s conquests were not yet at an end. Ulrich, the Duke of Carinthia and Carniola, had a very troublesome brother called Philip, who was generally at feud with some prince or other. Amongst his other enemies was the Patriarch of Aquileia, to whose office he desired to succeed. Ulrich, knowing Ottakar’s influence with the Pope and the ecclesiastics generally, tried to secure that influence in favour of the election of Philip to the patriarchate. Ottakar agreed, on condition that Ulrich would make him his heir in Carinthia and Carniola. Ulrich consented to this proposal; and, by Ottakar’s influence, the Chapter of Aquileia elected Philip Patriarch. Philip was apparently unaware of the bargain; and he was therefore extremely indignant, when, on Ulrich’s death, the King of Bohemia entered Carinthia and Carniola as the lawful heir of Ulrich. This bitterness was further increased when the Pope refused to confirm the election of the Chapter, and Philip found himself without either patriarchate or dukedom.