Examining the nature of the first regime ever to have effective control of the British Isles and the impact that it had on England, Ireland, Scotland and Wales and on Britain's international reputation, this study views the Cromwellian period as one of acheivement rather than merely a reactionary regime. It examines the aspirations of the Cromwellian Protectorate and underlines their commitment to a radical vision, despite the pressures and crises that the regime faced. It also considers the international dimension of the rules of Oliver and Richard Cromwell. The text contains many key documents of the period and a bibliographical essay, and is appropriate for A and AS level students as well as undergraduates and general readers.