The league was spearheaded by Bob Kap, Tex Schramm, and Al Davis, but failed to materialize.
Despite the league's goals, the IFL did not materialize - the Pro Football Researchers Association attributed this failure to Europe not being ready for American football, potential competition with the World Football League (WFL), a players' strike during the summer of 1974, and the recession that had been "gripping the nation".
[1] Another factor was the turmoil in Europe in 1974: Turkey had invaded Cyprus, the American ambassador to Cyprus had been assassinated, Basque separatists had assassinated the prime minister of Spain, and terrorist groups like the Red Brigades had engaged in kidnapping.
[2] This turmoil led the State Department to meet with NFL commissioner Pete Rozelle; the officials discouraged him from pursuing the league further.
The IFL also suffered a potentially fatal blow when Pan American World Airways, who Kap had brought on as a sponsor, pulled out of the project.