"Ragnar Lodbrok's saga" tells that Eysteinn was the king of Sweden and a good friend of Ragnar Lodbrok. Eysteinn had the most beautiful daughter named Ingeborg. He was also a devout pagan and there were so many blóts at Uppsala that no other place had ever been its equal. The Swedes worshiped a holy cow named Sibilja, and when the Swedes were attacked by enemies, they had the cow walk in front of the battle formation. The cow's magic was so great that when she began to bellow, the enemies began to fight between themselves.