 It has been suggested that Olaf's ambition was to rule a united Christian Scandinavia, and it is known that he made overtures of marriage to Sigrid the Haughty, queen of Sweden, but negotiations failed because of her steadfast pagan faith.Instead he made an enemy of her, and did not hesitate to involve himself in a quarrel with King Sweyn I of Denmark by marrying Sweyn's sister Tyra, who had fled from her heathen husband Burislav, the semi-legendary "King of Wends", in defiance of her brother's authority.Both his Wendish and his Irish wife had brought Olaf wealth and good fortune, but, according to the Sagas, his last wife, Tyra, was his undoing, for it was on an expedition undertaken in 1000 to wrest her lands from Burislav that he was waylaid off the island Svolder by the combined Swedish, Danish, and Wendish fleets, together with the ships of Earl Haakon's sons.