William Mayne, 1st Baron Newhaven

William Mayne, 1st Baron Newhaven PC (1722 – 28 May 1794), known as Sir William Mayne, Bt, between 1763 and 1776, was a British politician.

Mayne was the eldest son of the second marriage of William Mayne, of Powis Logie, Clackmannanshire.^[1] He was returned to the Irish House of Commons in 1761 for Carysfort, a seat he held until 1776.^[2] He was created a Baronet, of Marston Mortaine in the County of Bedford, in the Baronetage of Great Britain in 1763^[3] and sworn of the Irish Privy Council in 1766.^[4] In 1774 he was elected to the British House of Commons for Canterbury.^[5] Two years later he was elevated to the Peerage of Ireland as Baron Newhaven, of Carrick Mayne in the County of Dublin.^[6] He continued to represent Canterbury until 1780^[5] and then sat for Gatton until 1790.^[7]

Lord Newhaven married the Honourable Frances Allen, daughter of Joshua Allen, 2nd Viscount Allen, and co-heir of her brother John Allen, 3rd Viscount Allen, through which marriage he gained a considerable estate. They had one son who died in infancy. Lord Newhaven died in may 1794 when the baronetcy and barony became extinct.^[1]

References

1. ^ ^{a b} Burke, John. Burke, John Bernard. A Genealogical and Heraldic History of the Extinct and Dormant Baronetcies of England, p. 348.
2. ^ leighrayment.com Irish House of Commons 1692–1800
3. ^ London Gazette: no. 10304. p. 6. 12 April 1763.
4. ^ leighrayment.com Privy Counsellors
5. ^ ^{a b} Leigh Rayment's Historical List of MPs – Constituencies beginning with "C" (part 2)
6. ^ London Gazette: no. 11679. p. 1. 29 June 1776.
7. ^ Leigh Rayment's Historical List of MPs – Constituencies beginning with "G" (part 1)

Parliament of Ireland
Preceded by Richard Hull Stephen Trotter	Member of Parliament for Carysfort 1761–1776 With: Sir William Osborne, Bt 1761–1769 Sir Robert Deane, Bt 1769–1771 Sir Robert Deane, Bt 1771–1776	Succeeded by Thomas Osborne Warden Flood
Parliament of Great Britain
Preceded by Richard Milles William Lynch	Member of Parliament for Canterbury 1774–1780 With: Richard Milles	Succeeded by George Gipps Charles Robinson
Preceded by Robert Mayne William Adam	Member of Parliament for Gatton 1780–1790 With: Robert Mayne 1780–1782 Maurice Lloyd 1782–1787 James Fraser 1787–1790	Succeeded by John Nesbitt William Currie
Baronetage of Great Britain
New creation	Baronet (of Marston Mortaine) 1763–1794	Extinct
Peerage of Ireland
New creation	Baron Newhaven 1776–1794	Extinct