Life

Mostyn was born on 31 July 1673. He was the eldest son of Sir Thomas Mostyn, 2nd Baronet, of Mostyn

Mostyn

Mostyn is a small village in Flintshire, North Wales, lying on the estuary of the River Dee, and located near the town of Holywell.Mostyn once served as a port from which ferries used to sail to Dublin on the Liverpool-Dublin route...

 in Flintshire

Flintshire

Flintshire is a county in north-east Wales. It borders Denbighshire, Wrexham and the English county of Cheshire. It is named after the historic county of Flintshire, which had notably different borders...

, north Wales, and inherited the title on the death of his father in 1692. He attended the University of Oxford

University of Oxford

The University of Oxford is a university located in Oxford, United Kingdom. It is the second-oldest surviving university in the world and the oldest in the English-speaking world. Although its exact date of foundation is unclear, there is evidence of teaching as far back as 1096...

, matriculating

Matriculation

Matriculation, in the broadest sense, means to be registered or added to a list, from the Latin matricula – little list. In Scottish heraldry, for instance, a matriculation is a registration of armorial bearings...

 from Jesus College

Jesus College, Oxford

Jesus College is one of the colleges of the University of Oxford in England. It is in the centre of the city, on a site between Turl Street, Ship Street, Cornmarket Street and Market Street...

 in 1690. He was elected as MP

Member of Parliament

A Member of Parliament is a representative of the voters to a :parliament. In many countries with bicameral parliaments, the term applies specifically to members of the lower house, as upper houses often have a different title, such as senate, and thus also have different titles for its members,...

 for Flintshire

Flintshire (UK Parliament constituency)

Flintshire was a parliamentary constituency in North-East Wales which returned one Member of Parliament to the House of Commons of the Parliament of the United Kingdom from 1542 until it was abolished for the 1950 general election.- Boundaries :...

 in December 1701. In August 1702, he was elected MP for Flint

Flint Boroughs (UK Parliament constituency)

Flint Boroughs was a parliamentary constituency in north-east Wales which returned one Member of Parliament to the House of Commons of the Parliament of the United Kingdom and its predecessors, from 1542 until it was abolished for the 1918 general election.-Boundaries:From its first known general...

 and for Cheshire

Cheshire (UK Parliament constituency)

Cheshire is a former United Kingdom Parliamentiary constituency for the county of Cheshire. It was a constituency of the House of Commons of the Parliament of England then of the Parliament of Great Britain from 1707 to 1800 and of the Parliament of the United Kingdom from 1801 to 1832.As a county...

, choosing to represent Cheshire. He then alternated between representing Flint and Flintshire until his retirement in 1734. He was constable of Flint Castle

Flint Castle

Flint Castle located in Flint, Flintshire, was the first of a series of castles built during King Edward I's campaign to conquer Wales.The site was chosen for its strategic position in North East Wales...

 on two occasions, from 1702 to 1705 and then from 1715 to 1728. He was also Custos Rotulorum of Flintshire

Custos Rotulorum of Flintshire

This is a list of people who have served as Custos Rotulorum of Flintshire.* Sir Nicholas Hare bef. 1544–1557* John Griffith bef. 1558 – aft. 1579* Robert Dudley, 1st Earl of Leicester bef. 1584–1588...

 from 1714 to 1717 and from 1727 until his death in 1739. His eldest son, Sir Thomas Mostyn, 4th Baronet, inherited the title. Of his other sons, Roger was a Canon of Windsor

Dean and Canons of Windsor

The Dean and Canons of Windsor are the ecclesiastical body of St George's Chapel at Windsor Castle.-Foundation:The college of Canons was established in 1348 by Letters Patent of King Edward III. The college was formally constituted on the Feast of St...

, Savage

Savage Mostyn

Savage Mostyn was an officer of the Royal Navy who saw service during the War of the Austrian Succession and the Seven Years' War. He embarked on a political career, and was a Member of Parliament, Comptroller of the Navy, and one of the Lords of the Admiralty.Mostyn was born c. 1713 into a well...

 was a vice-admiral in the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

, and John

John Mostyn (governor)

General John Mostyn was a British soldier and colonial administrator. He was a younger son of Sir Roger Mostyn, 3rd Baronet.Mostyn served as Governor of Minorca for a ten year period between 1768 and 1778...

 was an officer in the British Army

British Army

The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

and a Member of Parliament.