I get that it's all collegiate football national champs (though I'd disagree that UCF should be included, so their inclusion threw me for a bit), but what does the geographic dispersion mean?

It's not just which is closest since USC wraps around BYU to some extent. And it's not based on recency since Princeton still has a huge area (including some of South Carolina over Clemson).

I so can't imagine it's most popular in an area because...again Princeton has a huge area. Plus other teams that are no longer FBS.

So I'm definitely interested - because there's some sort of information here beyond just a list of national champions, but I'm not sure what it is.