Ragnar's father was a prince of Norway. He married, however, a Danish princess, and thus Ragnar acquired a sort of hereditary right to a Danish kingdom--the territory including various islands and promontories at the entrance of the Baltic Sea. There was, however, a competitor for this power, named Harald. The Franks made common cause with Harald. Ragnar was defeated and driven away from the land. Though defeated, however, he was not subdued. He organized a naval force, and made himself a sea king. His operations on the stormy element of the seas were conducted with so much decision and energy, and at the same time with so much system and plan, that his power rapidly extended. He brought the other sea kings under his control, and established quite a maritime empire. He made more and more distant excursions, and at last, in order to avenge himself upon the Franks for their interposition in behalf of his enemy at home, he passed through the Straits of Dover, and thence down the English Channel to the mouth of the Seine. He ascended this river to Rouen, and there landed, spreading throughout the country the utmost terror and dismay. From Rouen he marched to Paris, finding no force able to resist him on his way, or to defend the capital. His troops destroyed the monastery of St. Germain's, near the city, and then the King of the Franks, finding himself at their mercy, bought them off by paying a large sum of money. With this money and the other booty which they had acquired, Ragnar and his horde now returned to their ships at Rouen, and sailed away again toward their usual haunts among the bays and islands of the Baltic Sea. This exploit, of course, gave Ragnar Lodbrog's barbarous name a very wide celebrity. It tended, too, greatly to increase and establish his power. He afterward made similar incursions into Spain, and finally grew bold enough to brave the Anglo-Saxons themselves on the green island of Britain, as the Anglo-Saxons had themselves braved the aboriginal inhabitants two or three centuries before. But Ragnar seems to have found the Anglo-Saxon swords and spears which he advanced to encounter on landing in England much more formidable than those which were raised against him on the southern side of the Channel. He was destroyed in the contest. The circumstances were as follows: