English politician and a zealous and courageous advocate of reform who more than once endured imprisonment for his radical views; he later lost interest in uprooting abuses and allied himself with the Conservative Party.

His marriage to a wealthy woman enabled Burdett to buy a seat in the House of Commons in 1796. Influenced by French Revolutionary ideals, he denounced Great Britain's war with France and attacked various wartime antiradical measures, especially the suspension (1794–1801) of the Habeas Corpus Act. He lost his seat in the Commons in 1806 because of an election dispute, but he was returned the next year by Westminster voters in what is said to be the first unquestioned radical (reform) victory in a British parliamentary election. In 1810 his speech against the imprisonment of another radical by the House of Commons was published in William Cobbett's radical Weekly Register, and Burdett himself was jailed for this alleged breach of parliamentary privilege. (It was against the law to publish parliamentary speeches.) In 1820 he was heavily fined and again imprisoned for censuring the government's action at St. Peter's Fields, Manchester, the “Peterloo (Manchester) Massacre” of a crowd assembled to hear speakers in favour of parliamentary reform (Aug. 16, 1819).

Burdett's enthusiasm for reform waned long before the Reform Bill of 1832 was enacted. From 1837 he represented a Wiltshire constituency rather than Westminster in the House of Commons, where he voted with the Conservatives and worked with their leaders.