William Mainwaring (English politician) Burdett. Mainwaring had previously resisted Burdett's calls for an inquiry into prison abuses, particularly at Coldbath Fields Prison. Mainwaring was defeated by Burdett but the election was declared void in 1804 and in the following contest William's son George Boulton Mainwaring was elected. The result was reversed in favour of Burdett in 1805 and the back in favour of Mainwaring Junior in 1806. Mainwaring did not contest the 1807 election and Burdett was not elected. He died in 1821, leaving one son. William Mainwaring (English politician) William Mainwaring (6 Oct 1735 – 28 February 1821) was the MP for Middlesex
William Mainwaring William Mainwaring William Henry Mainwaring (1884 – 18 May 1971) was a Welsh coal miner, lecturer and trade unionist, who became a long-serving Labour Party Member of Parliament. Both as a trade unionist and a politician he struggled, largely successfully to counter Communist influence. He was said to have spoken "with passion and fire on behalf of his fellow miners". Mainwaring was born in Swansea and went to local schools, leaving to work as miner in the South Wales coalfield. He was a member of the South Wales Miners' Federation, and through their sponsorship was able to continue his education