The sport got its start in the Ivy League and other northeast colleges. All of whom only generally began after September 1. So add on time to find a squad, and to get a schedule together, it's not uncommon to see early seasons begin in late September or October.

Then schedules only became longer as more schools started teams and the popularity grew. However for decades the end of terms and students going home put a hard limit for most games being played into December, save for special occasions like the early Bowls.

Profession leagues obviously did not need to deal with academic schedules. But at all levels the reason the season has now stretched from August to January/February is simply that people enjoy and want to consume more football.