The papers of Arthur William Mann (1901-1963), sportswriter, baseball executive, and author, span the years 1901-1969, with the bulk of the material concentrated in the years 1945 to 1962. The collection is composed of correspondence, drafts of books and articles, memoranda, notes, numerous newspaper clippings, printed matter, and miscellaneous items relating primarily to major league baseball, particularly to Branch Rickey and his contributions to the game. Also included are items relating to Rickey's innovations, such as organization of farm teams or minor league baseball clubs. Other items relate to boxing, football, the Olympic Games, and horse racing. The collection is arranged in six series: General Correspondence , Subject File , Writings File , Miscellany , Addition , and Oversize .

The numerous documents in the papers which focus on Branch Rickey are the result of Mann's decision to write a biography of Rickey. Many baseball and sports figures contributed information for this biography. In 1946, Mann became Branch Rickey's assistant with the Brooklyn Dodgers. Together they launched the major league career of Jackie Robinson in 1947 and later furthered the careers of other Black players. Mann's stand on matters such as expansion of major league baseball after World War II and the elimination of racial barriers brought him close to Rickey's pioneering views. There is also much material on Jackie Robinson, but very little on Mann himself.

Mann became one of the most respected sportswriters in America as a reporter for the New York World , the New York Herald Tribune , the New York Daily Mirror , and the New York Evening World . His work as an influential and prolific writer about sports is fully documented in the drafts of books and articles included in his papers.

The papers reflect other events that enabled Mann to become an effective, if controversial, baseball executive. These include his efforts in 1945 to integrate organized baseball and his "behind-the-scenes" action with Rickey to bring Jackie Robinson into the major leagues and to promote the careers of Donald Newcombe, Roy Campanella, Junior Gilliam (James William Gilliam), and Maury Wills.

Other items in the Mann Papers include a draft of The Real McGraw , a biography of John J. McGraw written by his wife Blanche Sindall McGraw and edited by Arthur Mann, a screenplay entitled "The Jackie Robinson Story," Jackie Robinson's statement before the House Un-American Activities Committee, numerous profiles or biographical sketches of prominent sports figures, and items concerning the Continental League of Professional Baseball Clubs as well as other material on baseball. Items relating to boxing include a file concerning Floyd Patterson and medical findings concerning "punch drunk" boxers.

Correspondents include William B. Arthur, William Edward Benswanger, Andrew Bernhard, Leonard Broom, Archibald J. Carey, Emanuel Celler, Happy Chandler, Bill Corum, Ed Fitzgerald, Ford C. Frick, Eric Frederick Goldman, James C. Hagerty, Harry Keck, Dan D. Mich, Westbrook Pegler, Branch Rickey, Ralph W. Sockman, and Casey Stengel.