National football league was known as American Professional Association (APFA) initially but later in 1922 it was renamed to be National Football League (NFA). The first president of this league was Jim Thorpe. As Jim Thorpe was a famous celebrity so his name brought the fame to this league and as a result NFL became the countries famous and the favourite sport.
Pro football was started in 1892 in Pittsburgh, Pennsylvania , Yale star William "Pudge" Heffelfinger was given a handsome sum of $500 for playing a single game for Allegheny Athletic Association on 12th November. Pro football faced many ups and downs and it was mainly played in small towns in western Pennsylvania and in Midwest.
Wen NFL started Buffalo All-Americans, Columbus Panhandles, Detroit Heralds and Chicago Tigers were its member. Only two of them exist today. The famous Dacatur Staleys in 1921 moved to Chicago and a year later it was named Bears and Chicago Cardinals is now called Arizona.