On 4th July 1910 Jack Johnson beat Jim Jeffries in the so-called fight of the century. It was a landmark fight that cemented Johnson's right to call himself the first black heavyweight champion of the world, busting stereotypes of black men as inferior in both body and mind. 100 years on, Gary Younge explores what the archives tell us about four boxers who span the century - Jack Johnson, Joe Louis, Muhammad Ali and Mike Tyson. How have they shaped, and been shaped by, our attitudes to black masculinity? Joe Louis was the first black boxer to be given a shot at the heavyweight title after Jack Johnson. We hear his iconic fight against German boxer Max Schmeling in 1938, which symbolised democracy vs facism and made Louis a national hero. Now one of the best-loved sportsmen of all time, Gary explores why early in his career Muhammad Ali was one of the most hated men in the US. We hear Ali on fighting form in an interview by David Frost in the run up to 1974's Rumble in the Jungle. By the end of the 20th century Mike Tyson seemed to confirm fears that black men were violent and out of control. How far was he in control of his public image? We hear the reaction to Tyson's infamous fight against Evander Holyfield in 1997, in which he bit off part of his opponent's ear. Gary interprets the archive with the help of experts including Ali biographer Mike Marqusee, Joe Louis' son Joe Louis Barrow and Ellis Cashmore, author of Tyson: Nurture of the Beast. Producer: Peggy Sutton A Somethin' Else production for BBC Radio 4.