The reign of this monarch was one of conquest and of prosperity. Soon after his accession, Absalom the archbishop led an armament against Bogislas duke of Pomerania, who exhibited ill-will to Denmark and her vassals, and obtained a complete victory over the enemy. During the two following years the warlike operations continued, and Bogislas at length was compelled to throw himself on the royal mercy. Besides offering a large quantity of gold, he did homage for all his possessions to Canute. The two dukes of Mecklenburgh were also reduced, and acknowledged fealty to him. The submission of two such provinces, which had been dependent on Henry the Lion, and had subsequently acknowledged the superiority of the empire, filled the king with so much pleasure, that he assumed the title of king of the Vandals. To this title he had, in his opinion, a two-fold claim: first, in virtue of the investiture of his ancestor, Canute duke of Sleswic, with the royal fief of the Obotrites[152]; and, secondly, in virtue of his present conquests. [Sidenote: 1183 to 1188.] To assume the feudal supremacy over these regions was a blow struck at the authority of the emperor Frederic Barbarossa. Between these potentates there was a misunderstanding from the very commencement of Canute’s reign. Frederic invited him to his court under the pretext of drawing more closely the amicable bonds which had been formed between him and Valdemar; but as the king suspected that this was only a lure to enforce the payment of homage, he evaded compliance. It soon appeared that such was indeed the intention; for he was formally summoned to visit the diet for that purpose. A second refusal to attend so exasperated Frederic that he threatened to confer the fief of Denmark on some other vassal. The king replied, that before he could give it, he must first take it. All negotiation being useless, the emperor offered the greatest insult to the majesty of Denmark, by sending back to her own country the sister of Canute, who had been betrothed to his second son, the duke of Swabia. From this moment the breach was irreparable; and the king turned with more zeal to the cause of his father-in-law Henry the Lion. [Sidenote: 1191 to 1202.]