During World War II the NFL's Eagles and Steelers merged into one team
The 1943 season was a tough one for the NFL, its fans, and America. At the height of World War II, Pennsylvania's two pro teams lost a number of players to military service. As a result, the two teams merged temporarily in order to play out the season, forming what the NFL called the "Phil-Pitt Combine." The sports press labeled the team the "Steagles," a name that fans quickly adopted. The season was saved.
The U.S. government fully supported the continuation of American sports to keep morale up on the homefront, but teams like the Steagles had rosters filled by players who didn't join the war effort because they were unfit for service, received a draft deferment, or were actually serving but on leave.
But in spite of the fact that the NFL needed eight teams to have a functional season, the Steagles almost didn't happen. Pittsburgh and Philadelphia were bitter rivals in the 1940s, and the men who would be co-head coaches hated each other.
Players received some public ridicule because of the general perception that if a player was fit enough to play football he should be fit enough to fight the Nazis. But most of the Steagles' players were declared physically unfit for service. The teams players also worked full time war production jobs. Football was not their only gig.
Philadelphia was hometown for the team and the team wore the Eagles' green and white colors. It was the only time in the history of the Steelers franchise that the team didn't wear black and gold. Pittsburgh owner Art Rooney did manage to get two home games played in Pittsburgh, however, both of which they won.
After a 2-0 start, the Steagles started to fall apart and by the end of the season, their record was a mediocre 5-4-1. They still hold the record for most fumbles in a winning game, where, against the New York Giants, they lost the ball ten times but still pulled out a 28-14 win, as lopsided a win as the U.S. had against the Axis.
In 2003, the Steelers hosted the Eagles on the 60th anniversary of the Steagles' formation and honored the surviving members who could make it. Philadelphia won that game 21-16.