Æthelred of Wessex of Mercia, appealed to him for help against the Vikings. Æthelred and his brother, the future Alfred the Great, led a West Saxon army to Nottingham, but there was no decisive battle, and Burgred bought off the Vikings. In 874 the Vikings defeated Burgred and drove him into exile. In 870 the Vikings turned their attention to Wessex, and on 4 January 871 at the Battle of Reading, Æthelred suffered a heavy defeat. Although he was able to re-form his army in time to win a victory at the Battle of Ashdown, he suffered further defeats on 22 January at
Alfred the Great 22 January. They were defeated again on 22 March at the Battle of Merton (perhaps Marden in Wiltshire or Martin in Dorset). Æthelred died shortly afterwards on 23 April. In April 871 King Æthelred died and Alfred succeeded to the throne of Wessex and the burden of its defence, even though Æthelred left two under-age sons, Æthelhelm and Æthelwold. This was in accordance with the agreement that Æthelred and Alfred had made earlier that year in an assembly at "Swinbeorg". The brothers had agreed that whichever of them outlived the other would inherit the personal property that King Æthelwulf had