Sir Roger Mostyn, 3rd Baronet

He was a Tory and a supported his father in law Daniel Finch, 2nd Earl of Nottingham before and after his marriage.

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.

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.

[3] Mostyn was appointed Constable of Flint Castle again in 1715 and held the post until he passed it on to his son in 1728.

[4] 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.

[5] His daughter Essex Mostyn (died 7 December 1764) married Robert Ker, second Duke of Roxburghe, and had issue.