Oliver Cromwell and the Puritan Victory in England.
Oliver Cromwell, a conservative and strict Puritan, made a name for himself by serving in the Long and Short Parliament in England. While he was serving in the Long Parliament, Charles I was in the process of trying to force a new prayer book, Catholicism, upon the people of Scotland. Cromwell and the Long Parliament stood steadfast until Charles was stopped. Charles went north and recruited an army to stand against Parliament and their forces. Parliament's forces were called Roundheads. Because of the threat of Charles I, Cromwell donated 60 horses to the Roundheads when the war broke out.
In the Battle of Edge Hill, the Royalist cavalry defeated the Roundheads. This prompted Cromwell to help train a professional cavalry in order to wage war against Charles I. In the process of leading the cavalry, Cromwell became known as "Ironsides" because of his undying fervor and strength towards the cause, and his leadership. Charles was defeated in 1645 by the Scots, who turned him over to Parliament. By the year 1646, Parliament was the sole leader of England. Cromwell managed to force the nobility into following him and Parliament. He also killed most of those who still held onto Catholicism as their faith, forcing Puritanism upon everone in England, Ireland, and Scotland. Cromwell managed to alienate the nobility and the army resulting in and unclear separation between the ancient constitution and traditional customs. .
I believe that Cromwell began with good intentions of trying to keep Charles I from forcing Catholicism upon Scotland, because Cromwell felt that Puritanism was a superior religion, and culture. He became so enveloped in the cause, however, that he managed to become just what he had waged war against Charles I for being. It was only a matter of time before the people of England realized this and decided that he was an unfit leader.