History of American Football Facts: From Invention To The Super Bowl
Fritz Pollard: An African American founding father of the NFL
Arizona Cardinals Team History and Timeline - Sports Illustrated
Jeopardy! - The NFL was formed #OTD in 1920. Fritz Pollard
There was a time NFL outgrew Canton; not anymore
Super Bowl history: How the NFL's first champion was declared
A look at the first decade of the NFL, the 1920s
Bears NFL franchise began in Decatur as the Staleys
What were the original NFL teams?
History of the NFL - National Football League
How the NFL took over America in 100 years - ESPN