Dr. Joseph Warren (June 11, 1741 – June 17, 1775) was an American doctor who played a leading role in American Patriot organizations in Boston in early days of the American Revolution, eventually serving as president of the revolutionary Massachusetts Provincial Congress. Warren enlisted Paul Revere and William Dawes on April 18, 1775, to leave Boston and spread the alarm that the British garrison in Boston was setting out to raid the town of Concord and arrest rebel leaders John Hancock and Samuel Adams. Warren participated in the next day's Battles of Lexington and Concord, which are commonly considered to be the opening engagements of the American Revolutionary War.