When it's 0 degrees outside, do you ever wonder why your ancestors decided to stick this out rather than move somewhere warmer? Why stay in the upper Midwest or New England when California, the Carolinas, or New Orleans beckoned?
In Wisconsin, the reasons people came and stayed had a lot to do with the kinds of people they were. Many of the state's first immigrants came from cold places originally (Norway, Germany, Finland, Canada) so a cold winter was nothing they didn't already know.
Warmer climates were also more susceptible to devastating outbreaks of disease, particularly yellow fever and malaria. Mosquitoes, the main carriers of these diseases, couldn't survive our cold winters so the outbreaks were never as severe or as long-lasting here as there.
Wisconsin also looked like home to many immigrants. Something about the lay of the hills and fields reminded many of them of Norway, Germany, or Switzerland. Sure, they'd been on a boat for a while and maybe the time away and the deliriousness of travel had twisted their memories, making anything seem inviting after time spent crammed on the lower decks of a ship, but countless letters home described a new place that recalled a beloved homeland. Norwegians wrote glowing letters about the area just west of Madison near Blue Mounds, Mt. Horeb, and the town of Vermont. The Swiss loved the green hills of today's Green County.
It also helped that many of the warmer places were not yet part of the United States in the 19th century or at least not yet as secure from potential Spanish takeover or other threats. Arizona didn't become a state until 1912. Texas wasn't sure it didn't want to be an independent republic until the mid-19th century. Things were more settled in the north for the most part.
So thank your ancestors for settling somewhere cold. They may have kept your bloodline safe from yellow fever and found an easier new start in a place that seemed a lot like home.