The Democratic Unionist Party (DUP) is a unionist political party in Northern Ireland favouring British identity. It was founded in 1971 during the Troubles by Ian Paisley, who led the party for the next 37 years. Now led by Arlene Foster, it is equal with Sinn Féin in having the most seats in the Northern Ireland Assembly, and it is the fifth-largest party in the House of Commons of the United Kingdom.

Ian Richard Kyle Paisley, Baron Bannside (6 April 1926 – 12 September 2014), was a loyalist politician and Protestant religious leader from Northern Ireland.

He became a Protestant evangelical minister in 1946 and remained one for the rest of his life. In 1951 he co-founded the fundamentalist Free Presbyterian Church of Ulster and was its leader until 2008. Paisley became known for his fiery sermons and regularly preached and protested against Roman Catholicism, ecumenism and homosexuality. He gained a large group of followers who were referred to as Paisleyites.

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