Henry Mainwaring in the King's cause in the English Civil War, was exiled to France, and died in poverty. He was buried at St. Giles' Church, Camberwell, London, on 15 May 1653. Mainwaring married a daughter of Sir Thomas Gardiner in 1630. She died in 1633. His brothers were Sir Arthur Mainwaring, Carver to Prince Henry, George Mainwaring, the defender of Tong Castle, and Sir Thomas Mainwaring, the Recorder of Reading. The Mainwaring family was old and distinguished, probably having arrived in England in the train of William the Conqueror (1066). Henry Mainwaring Sir Henry Mainwaring (1587–1653), was an English lawyer, soldier,
Sam Mainwaring life. Mainwaring was raised by his family as a Unitarian. He developed into a quiet yet persuasive public speaker and a tireless worker for activities which he believed important. Mainwaring was a member of the Amalgamated Engineering Union. Late in the 1870s, Mainwaring joined the East London Labour Emancipation League and was an early member of the Social Democratic Federation. However, this group proved to be a disappointment, failing to garner support of an appreciable section of the working class and was believed by many members to overly dominated by the intellectual pretensions and nationalist political views of its patriarch