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Sir Roger Mostyn, 3rd Baronet

1673 – 1739

Welsh politician;

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About Sir Roger Mostyn, 3rd Baronet

Lived 1673 – 1739 (aged 65). Sir Roger Mostyn, 3rd Baronet was a politician.

Sir Roger Mostyn, 3rd Baronet (31 July 1673 – 5 May 1739), of Mostyn Hall, Holywell, Flintshire, was a Welsh Tory politician who sat in the English and British House of Commons for 25 years from 1701 to 1735.

Early life

Mostyn was born on 31 July 1673, in Flintshire, north Wales. He was the eldest son of Sir Thomas Mostyn, 2nd Baronet, of Mostyn, and his wife Bridget Savage, daughter and heiress of Darcy Savage of Leighton, Cheshire. He matriculated at Jesus College, Oxford on 10 February 1690, aged 15.

On the death of his father in 1692, he inherited the Mostyn baronetcy and estates. Although the estates were extensive and with a good income, his extravagance and love of horse racing led him into financial difficulties and he needed to make a good marriage. He married Lady Essex Finch, the daughter of Daniel Finch, 2nd Earl of Nottingham (with £7,000) on 20 July 1703.

Career Mostyn was appointed Sheriff of Caernarvonshire for 1701. He was a Tory and a supported his father in law Daniel Finch, 2nd Earl of Nottingham before and after his marriage. At the second general election of 1701 he stood for Parliament at two seats. He was defeated in a contest at Cheshire, but was returned unopposed as Member of Parliament (MP) for Flintshire. In August 1702, he was returned unopposed for Flint and also elected MP for Cheshire, which he chose to represent. He was appointed Constable of Flint Castle in 1702.

He voted for tacking on the Occasional Conformity Bill to the Land-tax Bill in 1705 and this may have led to the loss of his seat and office of Constable. At the 1705 general election he was defeated in the poll at Cheshire but could fall back on the seat at Flint Boroughs where he was returned unopposed. He was returned unopposed for Flintshire in 1708 and 1710 and in 1711, he was appointed paymaster of the marines. He voted against the articles of commerce in 1713. At the 1713 general election, he was returned at Flint Boroughs. He was one of the four tellers of the exchequer from 30 December 1714 until 22 June 1716. He was also Custos Rotulorum of Flintshire from 1714 to 1717. In consideration of his services and the expenses he incurred as paymaster of the marines, he was allowed a sum of £300 for eight years. There is also among the 'Treasury Papers' a dormant warrant in favour of Mostyn as controller of the fines for the counties of Chester, Flint, and Carnarvon, dated 31 July 1704.

Death and legacy Mostyn died on 5 May 1739, at his seat in Carnarvonshire and was buried at Llanrhos, Caernarvonshire. By his wife, who died of smallpox on 23 May 1721, he had six sons and six daughters. He was succeeded by his eldest son, Thomas, with the death of whose grandson Thomas in 1831 the baronetcy became extinct. Three of his other sons were unmarried: Roger was a Canon of Windsor, Savage Mostyn was a vice-admiral in the Royal Navy, and John Mostyn was an officer in the British Army and a Member of Parliament. His daughter Essex Mostyn (died 7 December 1764) married Robert Ker, second Duke of Roxburghe, and had issue.

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Important facts

Birth century
Died
Occupation
Education
Jesus College
Positions held
Member of Parliament in the Parliament of England, Member of the 1st Parliament of Great Britain, Member of the 2nd Parliament of Great Britain, Member of the 3rd Parliament of Great Britain
Also known as
Sir Roger Mostyn, 3rd Bt.

People in Sir Roger Mostyn, 3rd Baronet's life

Named in this biography and alive at the same time

Contemporaries

People whose lives overlapped Sir Roger Mostyn, 3rd Baronet's

Frequently asked questions

Who was Sir Roger Mostyn, 3rd Baronet?

Welsh politician; (1673-1739)

When was Sir Roger Mostyn, 3rd Baronet born?

Sir Roger Mostyn, 3rd Baronet was born on 31 July 1673.

When did Sir Roger Mostyn, 3rd Baronet die?

Sir Roger Mostyn, 3rd Baronet died on 5 May 1739.

What was Sir Roger Mostyn, 3rd Baronet's occupation?

Sir Roger Mostyn, 3rd Baronet was a politician.

Sources & further reading

· Wikipedia: Sir Roger Mostyn, 3rd Baronet

· Wikidata: Q14945669

· DBpedia: Sir Roger Mostyn, 3rd Baronet

Cite this page

APA: Biography.guide. (2026). Sir Roger Mostyn, 3rd Baronet. https://biography.guide/sir-roger-mostyn-3rd-baronet/

MLA: "Sir Roger Mostyn, 3rd Baronet." Biography.guide, https://biography.guide/sir-roger-mostyn-3rd-baronet/.

Chicago: "Sir Roger Mostyn, 3rd Baronet." Biography.guide. https://biography.guide/sir-roger-mostyn-3rd-baronet/.

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