Question: Name the King of Wessex from 839 to 858 whose father, King Egbert, defeated Beornwulf of Mercia and who himself led the Battle of Aclea between the West Saxons and the Danish Vikings?
Sentence (from "Æthelwulf"): After 830, Egbert maintained good relations with Mercia, and this was continued by Æthelwulf when he became king in 839, the first son to succeed his father as West Saxon king since 641.
Relevant evidence: No