Oliver Cromwell was the leader of the Parliamentary forces to victory in the English Civil War. He led the Model New Army against King Charles I as result of Charles’ dismissal and blasé attitude of Parliament. 

Afterwards, Cromwell became a politician and held the special title of “Lord Protector” in the new republic. He gets a reputation as a dour man for his exertion on Puritan principles into law (no Christmas!). He was also disliked in Ireland for his cruel actions there. 