Cromwell is a 1970 British historical drama film written and directed by Ken Hughes. It is based on the life of Oliver Cromwell, who rose to lead the Parliamentary forces during the later years of the English Civil War and, as Lord Protector, ruled Great Britain and Ireland in the 1650s. It features an ensemble cast, led by Richard Harris as Cromwell and Alec Guinness as King Charles I, with Robert Morley as Edward Montagu, 2nd Earl of Manchester and Timothy Dalton as Prince Rupert of the Rhine.

Richard St John Francis Harris was an Irish actor and singer. Having studied at the London Academy of Music and Dramatic Art, he rose to prominence as an icon of the British New Wave. He received numerous accolades including the Cannes Film Festival Award for Best Actor, and a Grammy Award. In 2020, he was listed at number 3 on The Irish Times's list of Ireland's greatest film actors.