 He was a son of the English-born Henry Clews, a well-known and wealthy Wall Street investment banker, and Lucy Madison (née Worthington) Clews, a relative of U.S. President James Madison, and a direct descendant of American Revolutionary War brigadier general Andrew Lewis.His maternal grandfather, William H. Worthington, was a Union Army officer who died during the Civil War.One of Clews' aunts was married into the Vanderbilt family and another into the Astor family.