Accompanying his new liege Cnut, Eadric went on a campaign of plundering throughout England until in the summer of 1016, when a series of major battles were fought with Edmund Ironside, the successor of the deceased king Æthelred. The decisive battle was fought at Assandun on 18 October 1016. Eadric by that time had returned to his brother-in-law's side, but he fled the field with his men for uncertain reasons, though it was possibly pre-planned. After peace was made between Cnut and Edmund, Eadric was allowed to remain earl, however after a year Cnut had Eadric killed at London during the Christmas festivities in 1017.