It All Began in the 1930s
Prior to the inaugural National Football League draft in 1936, players were free to sign with any club. This tended to make the stronger teams even stronger and created much disparity in the NFL. On may 19, 1935, the league owners adopted a plan for a college player draft. Proposed by Bert Bell, the Eagles owner and future NFL commissioner, the plan called for teams to select players in inverse order of their finish the previous season.
The first draft had nine rounds and was increased to 10 in 1937. It was expanded to 20 rounds in 1939. Adding a twist to the procedure in 1938 and 1939, only the five teams that finished lowest in the previous season were permitted to make selections in the second and fourth rounds.