John Jones Maesygarnedd (c. 1597 – 17 October 1660) was a Welsh military leader and politician, known as one of the regicides of King Charles I following the English Civil War.

[1][2] A brother-in-law of Oliver Cromwell, Jones was a Parliamentarian and an avid republican at a time when most of Wales was Royalist, and became one of 57 commissioners that signed the death warrant authorising the execution of Charles I following his trial.

After the Restoration of the monarchy, Jones was one of few excluded from the general amnesty in the Indemnity and Oblivion Act, and was tried, found guilty, then hanged, drawn and quartered at Charing Cross.

During the English Civil War, Jones served in the Parliamentarian forces in Wales, and was described as a colonel in 1646 while negotiating the surrender of Anglesey in June 1646.

In 1648, Jones helped to suppress Sir John Owen's rising, and was thanked by the House of Commons for his share in the reconquest of Anglesey, and was voted £2,000 on account of his arrears of pay.

[9] His colleague, Edmund Ludlow, described him as "discharging his trust with great diligence, ability, and integrity, in providing for the happiness of that country, and bringing to justice those who had been concerned in the murders of English Protestants".

[11] He was accordingly set aside, and when in March 1656, there was a rumour that Jones was to be again employed in the Irish government, Henry Cromwell remonstrated with Thurloe against the choice, asserting that he was not only factious and disaffected, but "had acted very corruptly in his place".

[20] The main charge was that Jones had "openly and publicly owned that treacherous and traitorous act of part of the army in England in their unjust force put upon the parliament".

However, Jones seems to have been unaware of the danger he was in, making no attempt to flee, and was arrested on 2 June 1660, as he was quietly walking in Finsbury, and was committed to the Tower of London.

His forfeited estates in Wales went to the Duke of York (the future James II of England), while those in Ireland went to Arthur Annesley, 1st Earl of Anglesey.