Warwick , Robert Rich, Second Earl of (1587–1658), an English naval commander and colonial administrator. He helped promote the American colonies that became Massachusetts, Connecticut, and Rhode Island. On the outbreak of the Great Rebellion against Charles I, Warwick supported the parliamentary forces. In 1643 he became lord high admiral and head of a commission for governing the colonies. He defended freedom of worship in England and America. Because of his moderate stand in the struggle between Parliament and the king, he took no part in public affairs during the Commonwealth.