I served my LDS mission in the Minnesota Minneapolis Mission which covered parts of Wisconsin and also the UP of Michigan. I served in the one area that covered the UP. We were stationed 40 miles East in a town called Ashland, Wisconsin. Ironwood, Michigan is the first city you cross into when you get into Michigan. I never even asked myself why that part of Michigan wasn't just a part of Wisconsin. It's a good question.

Fun fact: Once you cross into Michigan, there is so much more snow. What separates Wisconsin and Michigan is something called the snowbelt. The side of it Michigan is on gets way more snow than the Wisconsin side. Crazy!

As for why the northeastern states are so much smaller, it's because they were originally colonies settled by the British. Also, much more populated per square mile than some of the bigger and more rural Western States. It is funny how that all evolved!

Explained well in this series that was on the History channel a decade ago:

How the States Got Their ShapesHow The States Got Their Shapes Starring Brian Unger Country of origin United States Original language English No. of seasons 2 (+ 1 special) No.en.wikipedia.org

Again, all based on Mark Stein's work referenced above.

Wherever you go, there you are.

The early colonies were carved out of land belonging to England. After the American Revolution, as U.S. borders expanded (as a result of, e.g., the Louisiana Purchase), American settlers moved westward relatively steadily, there was a lot more land available to occupy, and territorial boundaries were not determined by royal prerogative.

The current state of Wisconsin was part of what was once known as the Wisconsin Territory, which, before it became the Wisconsin Territory, was part of the Michigan Territory. Basically, over time, the territories in the Upper Midwest were cut into increasingly smaller sections, and when the state of Wisconsin was founded, it didn't have the option of absorbing the Upper Peninsula within its boundaries.