William Mayne, 1st Baron Newhaven

From 1757 to 1765, he was a director of the Royal Exchange Insurance Company and was recorded as a merchant in trade directories until 1780.

[2] Mayne was eager to enter Parliament and stood at the 1761 British general election at Canterbury where he was defeated.

[3] He was created a Baronet, of Marston Mortaine in the County of Bedford, in the Baronetage of Great Britain in 1763[4] and sworn of the Irish Privy Council in 1766.

[5] At the 1768 British general election he contested Malmesbury where he stood no chance against vested interests, after briefly considering Colchester.

[2] By 1774 Mayne had acquired a seat at Gatton where he was returned and was also elected Member of Parliament for Canterbury, where he chose to sit.