"Roundhead" was the name given to the supporters of the Parliament during the English Civil War. Also known as Parliamentarians, they fought against King Charles I and his supporters, the Cavaliers (Royalists), who claimed absolute power and the divine right of kings. The goal of the Roundhead party was to give the Parliament supreme control over executive administration.Most Roundheads appear to have sought a constitutional monarchy, in place of the absolutist monarchy sought by Charles I. However, at the end of the Civil War in 1649, public antipathy towards the king was high enough to allow republican Roundhead leaders such as Oliver Cromwell to abolish the monarchy completely and establish the republican Commonwealth. The Roundhead commander-in-chief of the first Civil War, Lord Fairfax, remained a supporter of constitutional monarchy, as did many other Roundhead leaders such as Edward Montagu and the Earl of Essex; however this party was outmanoeuvred by the more politically adept Cromwell and his radicals, who had the backing of the New Model Army and took advantage of Charles' perceived betrayal of England by allying with the Scots against Parliament.England's many Puritans and Presbyterians were almost invariably Roundhead supporters, as were many smaller religious groups such as the Independents. However many Roundheads were Church of England, as were many Cavaliers.Roundhead political factions included Diggers, Levellers and Fifth Monarchists.