The battle of Newbury was the turning point of the English Civil War. By August 1643 the King's cause was very much in the ascendant. Parliament armies had been crushed at Adwalton Moor and Roundway Down and the Royalists had taken Bristol. When they summoned Gloucester to surrender on 10 August the city's only hope was a Parliament relief army. The London Trained Bands joined the Earl of Essex's expedition and when battle was joined at Newbury the Londoners more than held their own against the best of the King's cavalry. With the citizens of London so firmly committed to Parliament's cause and the King's cavalry no longer invincible the balance of power had shifted irretrievably.