born Jan. 21, 1884, Wellesley, Mass., U.S.
died Aug. 26, 1981, Ridgewood, N.J.
U.S. civil-rights leader.
Born into an aristocratic Massachusetts family, Baldwin attended Harvard University and taught sociology at Washington University (1906–09) in St. Louis, where he also was chief probation officer of the city's juvenile court and secretary of its Civic League. When the U.S. entered World War I, he became director of the pacifist American Union Against Militarism, the predecessor of the American Civil Liberties Union (ACLU). As the ACLU's director (1920–50) and national chairman (1950–55), he made civil rights, once a predominantly leftist cause, a universal one.