During the Civil Wars of Charles I Wallingford Castle was held by the Royalists who wanted to guard the important river crossing point. Parliamentarian forces could not capture the castle and a siege only ended when the Royalist commander of the castle, Colonel Blagge, surrendered the castle after Charles himself had surrendered. In 1652, after being used as a prison for a short time, Cromwell decided that the castle should be totally destroyed so that it could not become a threat again.