John Slezak was born on 18 April 1896 in Stara Tura, in the province of Slovakia (later Czechoslovakia) in the former Austro-Hungarian Empire; immigrated to the United States in 1916; enlisted in the U.S. Army, 1917-1919; received a B.S. degree in mechanical engineering from the University of Wisconsin, 1923; was a mechanical engineer with the Western Electric Company, 1923-1930; was president, Turner Brass Works, Sycamore, Illinois, 1930-1953; served as colonel, Army of the United States, 1943-1946; was chief, Chicago Ordnance District, 1944-1946; as a civilian, was consultant to the Army and Navy Munitions Board, 1947; president and chairman of the board, Pheoil Manufacturing Company, Chicago, 1948-1953; director, National Association of Manufacturers, 1952-1953; was Assistant Secretary of the Army (Materiel), 4 May 1953-7 February 1954; was Under Secretary of the Army, 8 February 1954-16 January 1955; president, Association of the U.S. Army, 1955-1957; chairman of the board, Kable Printing Company, Mount Morris, Illinois, 1947-1972; director, Hazeltine Corporation, Clayton Mark Company, Roper Corporation, Hazeltine Research, Inc., Western Publishing Company; was chairman of the Reserve Forces Policy Board, Department of Defense, 1957-1978; trustee, Illinois Institute of Technology, 1949-1984, and the Foundation for Economic Education, 1955-1967; died on 14 April 1984 at Sycamore, Illinois.