It was more successful than earlier rivals to the NFL, including not only the organizations founded in 1926, 1936, and 1940, respectively, under the AFL name, but also the later All-America Football Conference, which existed between 1944 and 1950, but conducted operations only between 1946 and 1949.

The transformation of the struggling Titans into the New York Jets under new ownership, including the signing of University of Alabama star quarterback Joe Namath, further solidified the league's reputation among the major media.

The ten AFL franchises joined three existing NFL teams—the Baltimore Colts, the Cleveland Browns, and the Pittsburgh Steelers—to form the merged league's American Football Conference.

[3] When Hunt, Adams, and Howsam were unable to secure a controlling interest in the Cardinals, they approached NFL commissioner Bert Bell and proposed the addition of expansion teams.

Within weeks of the July 1959 announcement of the league's formation,[8][9] Hunt received commitments from Barron Hilton and Harry Wismer to bring teams to Los Angeles and New York, respectively.

The older league also announced on August 29 that it had conveniently reversed its position against expansion, and planned to bring new NFL teams to Houston and Dallas, to start play in 1961.

Los Angeles Chargers owner Barron Hilton demanded that a replacement for Minnesota be placed in California, to reduce his team's operating costs and to create a rivalry.

[19] The AFL began regular-season play (a night game on Friday, September 9, 1960) with eight teams in the league – the Boston Patriots, Buffalo Bills, Dallas Texans, Denver Broncos, Houston Oilers, Los Angeles Chargers, Titans of New York, and Oakland Raiders.

Raiders' co-owner Wayne Valley dubbed the AFL ownership "The Foolish Club", a term Lamar Hunt subsequently used on team photographs he sent as Christmas gifts.

Attendance was so low for home games that team owner Harry Wismer had fans move to seats closer to the field to give the illusion of a fuller stadium on television.

The Titans were sold to a five-person ownership group headed by Sonny Werblin on March 28, 1963, and in April the new owners changed the team's name to the New York Jets.

Lamar Hunt felt that despite winning the league championship in 1962, the Texans could not sufficiently profit in the same market as the Dallas Cowboys, which entered the NFL as an expansion franchise in 1960.

On January 29, 1964, the AFL signed a lucrative $36 million television contract with NBC (beginning in the 1965 season), which gave the league money it needed to compete with the NFL for players.

Pittsburgh Steelers owner Art Rooney was quoted as saying to NFL Commissioner Pete Rozelle after receiving the news of the AFL's new TV deal that, "They don't have to call us 'Mister' anymore".

League expansion was approved at a meeting held on June 7, and on August 16 the AFL's ninth franchise was officially awarded to Robbie and entertainer Danny Thomas.

That following May, Wellington Mara, owner of the NFL's New York Giants, broke a "gentleman's agreement" against signing another league's players and lured kicker Pete Gogolak away from the AFL's Buffalo Bills.

"[46] The AFL added its tenth and final team on May 24, 1967, when it awarded the league's second expansion franchise to an ownership group from Cincinnati, Ohio, headed by NFL legend Paul Brown.

However, on November 17, 1968, when NBC cut away from a game between the Jets and Raiders to air the children's movie Heidi, the ensuing uproar helped disprove the notion that fans still considered the AFL an inferior product.

Jets quarterback Joe Namath recalled that in the days leading up to the game, he grew increasingly angry when told New York had no chance to beat Baltimore.

He helped persuade the Pittsburgh Steelers (the Browns' archrivals) and Baltimore Colts (who shared the Baltimore-Washington market with the Washington Redskins) to follow suit, and each team received US$3 million to make the switch.

Hunt's vision not only brought a new professional football league to California and New York, but introduced the sport to Colorado, restored it to Texas and later to fast-growing Florida, as well as bringing it to Greater Boston for the first time in 12 years.

As part of the merger agreement, additional expansion teams would be awarded by 1970 or soon thereafter to bring the league to 28 franchises; this requirement was fulfilled when the Seattle Seahawks and the Tampa Bay Buccaneers began play in 1976.

Kevin Sherrington of The Dallas Morning News has argued that the presence of AFL and the subsequent merger radically altered the fortunes of the Pittsburgh Steelers, saving the team "from stinking".

The $3 million indemnity that the Steelers received for joining the AFC with the rest of the former AFL teams after the merger helped them rebuild into a contender, drafting eventual-Pro Football Hall of Famers like Terry Bradshaw and Joe Greene, and ultimately winning four Super Bowls in the 1970s.

While the NFL was still emerging from thirty years of segregation influenced by Washington Redskins' owner George Preston Marshall, the AFL actively recruited from small and predominantly black colleges.

In the league's first years, players such as Oilers' George Blanda, Chargers/Bills' Jack Kemp, Texans' Len Dawson, the Titans' Don Maynard, Raiders/Patriots/Jets' Babe Parilli, Pats' Bob Dee proved to be AFL standouts.

Other players such as the Broncos' Frank Tripucka, the Pats' Gino Cappelletti, the Bills' Cookie Gilchrist and the Chargers' Tobin Rote, Sam DeLuca and Dave Kocourek also made their mark to give the fledgling league badly needed credibility.

Players who chose the AFL to develop their talent included Lance Alworth and Ron Mix of the Chargers, who had also been drafted by the NFL's San Francisco 49ers and Baltimore Colts respectively.

In it, Abner Haynes tells of how his father forbade him to accept being drafted by the NFL, after drunken scouts from that league had visited the Haynes home; the NFL Cowboys' Tex Schramm is quoted as saying that if his team had ever agreed to play the AFL's Dallas Texans, they would very likely have lost; George Blanda makes a case for more AFL players being inducted to the Pro Football Hall of Fame by pointing out that Hall of Famer Willie Brown was cut by the Houston Oilers because he couldn't cover Oilers flanker Charlie Hennigan in practice.

Additionally, many prominent coaches began their pro football careers as players in the AFL, including Sam Wyche (Cincinnati Bengals), Marty Schottenheimer (Buffalo Bills), Wayne Fontes (Jets), and two-time Super Bowl winner Tom Flores (Oakland Raiders).