The first 'global' sporting superstar, who first resembles what we now consider a 'superstar', was Jem Mace.
John L. Sullivan may have been the most famous athlete, let alone the most famous boxer, of the 19th Century. - Chuck Johnston
Most famous fighters by decade 1890's: John L. Sulivan 1900's: Bob Fitzsimmons 1910's: Jack Johnson 1920's: Jack Demspey 1930's: Joe Louis 1940's: Joe Louis / Sugar Ray Robinson 1950's: Rocky Maricano / Sugar Ray Robinson 1960's: Cassuis Clay 1970's: Muhammad Ali 1980's: Sugar Ray Leonard / Mike Tyson 1990's: Oscar De La Hoya / Mike Tyson / Roy Jones Jr. 2000's: Manny Pacquaio / Floyd Mayweather Jr. 2010's: Floyd Mayweather Jr.
Crossover - the first names on my list would be Ali, Leonard, Tyson and DeLaHoya. These are names in the super heavy media that broached the mainstream barrier and made these recognisable and marketable names. Of course many names can follow like the aforementioned Louis and Robinson, but when you can get to the point of pop-star status you are talking marketing. John Conteh of England and Mando Ramos of the west coast enjoyed this in their respective locales, but due to shortened careers their names never broadened beyond their bailwick.
Joe Louis was the heavyweight champion for 11 years! He KO'ed everything moving during those years. Seriously can you imagine if MIke Tyson spanned his reign that long? Joe Louis was the champion for some peoples entire childhood. He had to be the most famous man in the connected world.
One. Muhammad Ali.I saw his photo in the houses in remote villages inTunisia,Algeria,Morocco,Greece,Turkey,Sicily etc .He is the only real crossover star who was truly world famous and recognized everywhere.
Like it or not, if you haven't made it in America, you haven't made it. That's just a fact, however unsavory it may be to you.
Don't make things up about Russia. Ali may have been shown on TV a few times, but few people remembered him or his name.