Bryant's professional papers reflect his position as a surgeon in the Spanish and American War, his medical service with the Red Cross in the first World War, and his scholarly interests as an active member of numerous medical societies and author of several medical works, 1861-1956. The personal papers includes Bryant's genealogical research on the Bryant and allied families of Mason, Smith, and Sohier, 443 B.C.-1956. Most of the research is in the form of correspondence and notes, 1902-1935, between Bryant and George W. Chamberlain. Following the genealogical research is biographical material and family papers on Bryant's immediate family, especially his grandfather, John Bryant, and his father and mother, Henry and Elizabeth Brimmer (Sohier) Bryant, with less material on Bryant's brothers, John and Henry, 1945-1957. Collection concludes with 380 photographs, 1853-1952, of William S. Bryant, his relatives and friends.