1) The All American Football Conference (1946-'49). The first major challenger to NFL supremacy, and perhaps the one with the best chances, the AAFC took advantage of the post-war boom and air travel to mount a major challenge to the football establishment. In an era where pro football was small potatoes compared to college football (many college stars actually didn't go professional, making better money in business) and baseball, both leagues were nearly bled white by a fierce bidding war for players. In the end, the NFL hung on a little longer to win, but the peace deal still forced them to accept 3 teams from the AAFC. One of those teams was the Cleveland Browns, who shattered any beliefs that the AAFC had been inferior by playing in the NFL Championship game their first 5 years in the league and winning it twice.
2) American Football League (1960-'69). Barely a decade removed from their battle with the AAFC, the NFL had another contender step into the ring. The American Football League thrived by planting most of its teams in untapped markets and taking full advantage of the truckloads of money the new medium of TV provided. The brash and colorful AFL contrasted sharply with the stoic and traditional NFL, and their rivalry eventually led to the establishment of the Super Bowl. Again, a bidding war ensued. Although both leagues remained viable, the AFL didn't see the point of prolonging the battle and agreed to a full merger under the NFL banner. It didn't go into effect, however, until the AFL had gone 2-for-4 in the Super Bowl, ending any NFL mockery.
3) United States Football League (1983-'85). A unique challenger, the USFL went with a strategy of 'compete by not competing'. The league played spring and summer ball to avoid fan conflicts, and had strict salary caps to prevent a bidding war with the NFL. The strategy worked for a while, and the league had an average attendance of 25,000+ in 1983. Two flagship franchises, the Tampa Bay Bandits and Denver Gold, even managed to average roughly 40,000 fans a game. However, money remained a problem, and expansion, mergers, and teams folding changed the shape of the league every year. By 1985, only 5 of the founding 12 USFL teams were functioning in their original form. The man who normally gets the blame for finally killing the league is Donald Trump. He broke the salary cap in an attempt to rapidly build his New Jersey Generals into contenders -triggering wild spending in the rest of the league- and convinced a majority of owners to move the league to fall play and sue the NFL. News of the impending showdown devastated USFL teams in NFL markets, and the lawsuit netted the league a paltry $1 in damages. The bankrupt USFL threw in the towel after the close of the '85 season.
4) NFL Europe (1995-2007). Envisioned as a way for the NFL to increase it's global footprint and establish a developmental league at the same time, the NFL Europe was formed from the ruins of the short-lived World League of American Football (1991-'92). Although bankrolled by football's superpower, the NFL-E was plagued by lack of fan interest from Day 1. Out of 6 charter members, only 2 of them -the Amsterdam Admirals and the Rhein Fire- managed to survive the league's full run. Teams were established in the UK, Spain, Germany, and the Netherlands, but by 2007, 5 of the 6 teams were in Germany, and the Amsterdam squad (which only averaged 11,000 fans) was likely only kept afloat to give the 'Europe' in the league's name a shred of legitimacy. With the NFL-E deep in the red and going nowhere fast, the father league shut it down on June 29th, 2007.
5) XFL (2001). Although commonly referred to as the 'Xtreme Football League', the league never actually gave the acronym an official meaning. So now you know. Created by the Chairman of the Board of Directors of the WWE, the XFL was meant to be the NFL's edgier cousin, with team names like 'Hitmen', 'Rage', 'Demons', and 'Maniax'. Trash talk was integral, penalties were nearly abolished, and the cheerleaders were a whole lot closer to strippers than Baylor Songleaders. Also, the league's ties to pro wrestling cast doubts on how legitimate the already poor quality of play was. All in all, the XFL's brand of 'gangsta' football failed to catch on and the league folded after one season.
Frankly, I'm not crying any tears for this one's fate.
