1911 Encyclopædia Britannica/Burgred
BURGRED, king of Mercia, succeeded to the throne in 852, and in 852 or 853 called upon Æthelwulf of Wessex to aid him in subduing the North Welsh. The request was granted and the campaign proved successful, the alliance being sealed by the marriage of Burgred to Æthelswith, daughter of Æthelwulf. In 868 the Mercian king appealed to Æthelred and Alfred for assistance against the Danes, who were in possession of Nottingham. The armies of Wessex and Mercia did no serious fighting, and the Danes were allowed to remain through the winter. In 874 the march of the Danes from Lindsey to Repton drove Burgred from his kingdom. He retired to Rome and died there.
See Saxon Chronicle (Earle and Plummer), years 852-853, 868, 874.