Oliver Cromwell was the only republican ruler in English history. He rose from being an obscure country farmer, through a brilliant career as a soldier, to become head of state as Lord Protector after the revolution of 1649. But although we have extensive records of his letters and speeches, much about his career and his inner motives remains mysterious. Through a wide variety of primary sources, some previously unpublished, this book considers what drove Cromwell as a soldier, politician, statesman and religious visionary; how he saw his own mission, and how others viewed him. Ultimately we confront a haunting question: was Cromwell a man driven by visions of a free and just society, or by ambition and self-interest; a principled defender of civil and religious liberties, or a bigot and tyrant? This book explores these issues and leaves students to make up their own minds.