While the AFL, and others like it, catered to the British and Irish expatriate communities, there were few opportunities available to the rest of Chicago's many immigrant groups to play organized, competitive soccer.

That year the ISFL, with Frank Foldi as its president, was created to address the lack of league opportunities for non-British teams.

World War II hit the NSL hard as most of the top players were inducted in the armed forces.

A few years later, another wave of immigrants, this time Eastern Europeans fleeing communism, brought another fresh group of talented players into the NSL.

[2] These waves of immigration led to an expansion of the league into multiple divisions including junior and youth teams.

The NSL, in response to the COVID-19 pandemic in March 2020, cancelled the last two rounds of matches in indoor play as well as the playoffs.

[4] This marked the first time in the NSL's century-long history since World War II a season would not be played.