In the two seasons of the league’s existence, the Chiefs fielded a competitive team. In 1940, the team scored the most points and gave up the fewest over the course of the season, but lost to Columbus in the final game to give the league championship to the Bullies. The following year, the Chiefs and the Bullies were joined by the New York Americans in a three-way race for the championship, with the Chiefs' continuing inability to defeat the Bullies (losing in Columbus and tying in Milwaukee) led to Columbus repeating as AFL champions and Milwaukee finishing third.
For the two years of the league’s existence, the Chiefs were a popular draw as they played in Wisconsin’s largest stadium. The AFL had accepted the 1941 entrance of a new Detroit team and deferred it until 1942, but the Pearl Harbor attack and the subsequent U.S. entry into World War II put all plans for football to a halt. In September 1942, league president William B. Cox announced the suspension of league activities until after the war, but the league – and the Chiefs – never returned.