Which leaves the question on every body's lips: Who was Syr Siôn Trefor?
This is the answer from The Dictionary of Welsh Biography
Sir JOHN TREVOR (1638 - 1717), speaker and judge, was the second son of John Trevor (d. c. 1643). His father dying in his early boyhood, he was befriended by his uncle Arthur Trevor, who prepared him for entry to the Inner Temple (Nov. 1654), whence he was called to the Bar in May 1661.
Six years later he accompanied his kinsman and namesake, Sir J. Trevor ‘III’ of Trevalun, on an embassy to France, was knighted on 29 Jan. 1671, and in 1673 entered Parliament, sitting for English pocket boroughs till 1681, and failing to secure election for Montgomery in 1679.
He combined a fulsome support of the royal prerogative and single handed defence of his unpopular cousin and patron Jeffreys with an aggressive Protestantism, resulting in his chairmanship of committees like those on the growth of popery (29 April 1678) — inspired by John Arnold, and issuing in the martyrdom of David Lewis and other South Wales catholics — and on the impeachment of Powis and the other popish lords.
Living mainly in London, he acquired a country house at Pulford, lower down the Dee than the family seat, until the death of his elder brother made him heir to the latter, probably before the violent county election of March 1681, when he revived the old family feud by capturing Denbighshire from the Whiggish but territorially far more powerful Myddeltons, who challenged him to a duel for calling the Roundhead Sir Thomas a traitor.
He became mayor of Holt next year, and in 1684 was put on a commission of enquiry into concealed crown lands in Denbighshire.
On James II's accession, Beaufort, as President of Wales , intervened, at the prompting of the king and Jeffreys, to heal the feud, with the result that Myddelton was returned unopposed for the county and Trevor for the borough, of which he was promptly made a burgess. Trevor had his revenge when a quarter of a century later he helped to ruin the Edisbury'sclients of the Myddeltons, by foreclosing on their Erddig estate, of which he was a principal mortgagee.
In 1685 he was elected Speaker of the House (19 May), and appointed Master of the Rolls (20 Oct.), and added to the privy council , with two Dissenters to offset his stiff Anglicanism , on 6 July 1688; he was also given the joint constableship of Flint castle (1687) and the office of ‘ custos rotulorum ’ of Flintshire (Dec. 1688), remaining true to James even after his first flight. He therefore lost his offices at the Revolution , but was again returned to parliament for an English pocket borough and resumed his speakership (May 1690).
Winning the favour of William III by his success in ‘managing’ the Tories, he was restored to the privy council (1 Jan. 1691), made first commissioner of the Great Seal during the vacancy of 1690-93 , and re-appointed Master of the Rolls on 13 Jan. 1693, but in 1695 he was deposed from the speakership (12 Mar.) and expelled the House (16 Mar) for bribery, only a few weeks after he had been within sight of the woolsack.
His Welsh offices were restored in 1705 . He d. in London , 20 May 1717 , leaving a reputation for legal knowledge and judicial impartiality in sharp contrast with his political venality. He was a benefactor of many county charities , including Denbigh grammar school . His portrait is preserved at Brynkynallt. He m. Jane , daughter of Sir Roger Mostyn and widow of Roger Puleston of Emral . With the death, in 1762, of his eldest son, who unsuccessfully contested Dnbigh boroughs in the Tory interest in 1741, the male line came to an end
Hm! A Welsh man was the last speaker to feel the parliamentary boot up his backside, a Scot is the latest recipient. I feel an anti Celtic minorities rant brewing!!!!