Sir Thomas Myddelton, 1586-1666
First took up arms at the age of 56 and became major-general of Parliament's forces in north Wales, but later supported Booth's Uprising against the Commonwealth.
Thomas Myddelton was born in London in July 1586, the only son of a wealthy merchant and alderman, also called Sir Thomas Myddelton, who became Lord Mayor of London in 1613. Myddelton attended Queen's College, Oxford, and Gray's Inn. In 1612, he married Margaret Savile, daughter of George Savile of Wakefield. At the time of his marriage, Myddelton's father settled upon him the estate of Chirk Castle in Denbighshire, which the elder Myddelton had purchased in 1595. Margaret died in childbirth in 1613, and Myddelton married Mary Napier (d. 1675), daughter of Sir Robert Napier of Luton, Bedfordshire, in 1617. In the same year, Myddelton was knighted by King James I.
Myddelton settled at Chirk where his great wealth made him a leading figure in local government. He extended his estates in north Wales with the purchase of Ruthin Castle in 1632. Myddelton was elected MP for Denbighshire in the Long Parliament where he sat on several committees dealing with finance and religion. His principal concern was the perceived threat from foreign Catholic influences.
In June 1642, Myddelton was sent to put the Militia Ordinance into force in Denbighshire. However, he encountered strong opposition from Welsh Royalists, who seized his estates at Chirk and Ruthin. Aged fifty-six when the First Civil War broke out and with no military experience, Myddelton nevertheless took an active part in the war. He was commissioned major-general of Parliamentarian forces in north Wales.

Unable to march directly into Wales, Myddelton joined forces with Sir William Brereton and the Cheshire Parliamentarians in August 1643. After campaigning against the Shropshire Royalists, Brereton and Myddelton mounted a spectacular invasion of north Wales in November 1643. Their success was short-lived, however, and they were forced back into Cheshire by the arrival of Royalist reinforcements from Ireland.
During 1644, Myddelton's forces raided Royalist towns and garrisons in mid-Wales and succeeded in capturing Montgomery Castle in early September. Lord Byron marched to recapture the castle but Myddelton co-operated with Brereton and Sir John Meldrum to inflict a major defeat on the Welsh Royalists at the battle of Montgomery on 18 September 1644. Two weeks later, Myddelton secured his hold on mid-Wales with the capture of Powis Castle. However, a lack of men and supplies prevented him from advancing into north Wales or from recapturing his estates at Chirk and Ruthin. His command ended when the Self-Denying Ordinance came into force in June 1645.
With the ending of the war, Myddelton's estates were restored to him and he returned to his parliamentary duties and the work of local government. He was again entrusted with the defence of north Wales during the Second Civil War, but left the campaigning to his brother-in-law Thomas Mytton. Myddelton opposed the King's trial and was expelled from Parliament in Pride's Purge of December 1648, after which he became increasingly disillusioned with the Parliamentarian cause. Rumours that he was in communication with Charles II in 1651 led the Council of State to put a garrison into Chirk Castle, which was not withdrawn until Myddelton had given a public assurance of his loyalty to the Commonwealth.

In August 1659, Myddelton took part in Booth's Uprising in Cheshire and north Wales, declaring for Charles II at Wrexham before joining Sir George Booth at Chester. He was present at Winnington Bridge, where the insurgents were defeated by Colonel Lambert. Myddelton evaded capture but his estates were ordered to be sequestered and Chirk Castle to be demolished. However in February 1660, before the order could be completed, he was recalled to Westminster under the protection of General Monck with the other MPs expelled in Pride's Purge. The vote for his sequestration was suspended but the dismantling of Chirk had been carried far enough to make it uninhabitable until 1672, so Myddelton's family occupied a nearby manor house at Cefn-y-wern. He sat as MP for Denbighshire in the Convention Parliament and again proclaimed Charles II at Wrexham in May 1660.
Despite the expense and privations of the civil wars, Myddelton was one of the richest men in the kingdom when he died in January 1667. He had doubled the size of his estate he inherited and profited from rents, cattle dealing, coal and iron mining. Myddelton and his second wife had seven sons and six daughters. His eldest son Thomas was made a baronet in 1660.
Sources:
A.H. Dodd, Sir Thomas Myddelton 1586-1666 Welsh Biography Online
Peter Gaunt, A Nation Under Siege, the civil war in Wales 1642-48, (HMSO 1991)
J.R. Phillips, Memoirs of the the Civil War in Wales and the Marches vol i (London 1874)
J. Gwynn Williams, Sir Thomas Myddelton, Oxford DNB, 2004