This is a compilation of all USA states governorships showing which parties held which states and how that changed throught american history. Idea to make this when I once try to find similar thing on internets, but I could not so I decideded that I might as well make one myself.
Impressive accomplishment. I have two corrections to make, that is the "Know-Nothing" Party was technically the American Party, and the Bull Moose Party was technically the Progressive Party. The former came to be known as the know-nothing party because its members were trained to answer whenever someone asked about who was in it, "I know nothing." One mild criticism, some of your color selections are very close so it's hard to tell which is which. Otherwise, excellent job.
