Essex believed he had established a commanding lead over Charles and, not wishing to drive his hungry army too hard, slowed his pace on the march to Swindon. He was further slowed after Swindon when Rupert's cavalry caught up, and the resulting Battle of Aldbourne Chase on 18 September allowed the rest of the Royalist army to close the distance. Charles finally brought Essex to battle on 20 September in the First Battle of Newbury, but failed to defeat him, allowing the Parliamentarians to reach the safety of their London stronghold four days later.