Having led the parliament of England’s armies against King Charles I, and seen to it that the king was executed, Oliver Cromwell went on to rule the British Isles as Lord Protector from 1653 to 1658. But how did Cromwell rise to play his part in the overthrow of the monarchy? Why did he take on Ireland and Scotland? And why is he now considered one of the ten greatest Britons of all time? Rob Weinberg asks the big questions about this controversial figure to historian Dr. Rebecca Warren.