Partly as a result of his rivalry with Coningsby for control of Herefordshire, Hereford was surrendered to a small Parliamentarian force in 1643.

During the English Civil War, the castle was raised to the ground, by Parliamentarian forces.

The first battle was a minor royalist victory on 9 December 1642, when a small Royalist force put to flight a smaller Parliamentarian force.

On the night of 4 September, a Parliamentarian force of 400 infantry equipped with ladders and backed by cavalry set out to attack the castle.

He was killed in 1645 when a Parliamentarian force besieged the Royalist-held town of Bridgwater in Somerset.

In 1650 he won a second small (though inconsequential) victory over an English Parliamentarian force during the battle of Tecroghan with some aid from Ulick Burke.

The Parliamentarian force lost twenty men.

In the afternoon Parliamentarian forces drove off 50 cattle grazing in fields outside the East Gate.

The Parliamentarian force was led by an experienced Scottish professional soldier, Sir John Meldrum.

In that year he edited the Souldier's Pocket Bible, a popular Biblical anthology designed for the Parliamentarian military forces.