Battle of Reading (871) a camp at Reading, defended by the Thames and Kennet rivers on two sides, and by a rampart on the western side. Three days after their arrival, a party of Danes rode out towards nearby Englefield, where a West Saxon force under the command of Æthelwulf, the Ealdorman of the shire, was waiting for them. In the ensuing Battle of Englefield many of the Danes were killed, and the rest driven back to Reading. Four days later, Æthelwulf had been joined by the main West Saxon army, led by King Æthelred and his brother, Alfred the Great. The entire Saxon
Halfdan Ragnarsson led by Bagsecg, bolstering the ranks of Halfdan's army. According to the "Anglo-Saxon Chronicle", the Danes battled the West Saxons nine times, including the Battle of Ashdown on 8 January 871. However, the West Saxons could not be defeated, and Halfdan accepted a truce from Alfred, newly crowned king of Wessex. The Army retreated to the captured town of London and stayed there over the winter of 871/872. Coins minted in London during this period bear the name Halfdan, identifying him as the leader of the army. In autumn of 872 the Army returned to Northumbria to quell a revolt