You are correct - Missouri might be predominantly Midwestern culture, but there's still a lot of Southern culture and dialect in it (even stretching from the east end to the west end around Joplin). A good hour+ south of St. Louis, sure, but it stretches from the east (adjacent to Cairo, IL) all the way to the west end past Joplin. That's circa 330 miles in width complemented with the southern 35% of the state. Southern culture and dialect is a far second in the state, but they're moreso a unique variation to the SEC rather than an outlier (which they're definitely not IMO). There are a lot of roots in common, just depends where in the state you're looking. I am from SE Missouri, 100 miles straight south of St. Louis. The culture is very mixed in that area but is definitely "southern" starting just 30 miles south of us. Also, Missouri was neither slave nor free. It was a constant debate that was never really settled. As a matter of fact, we had two governors during the Civil War, one confederate and one union. There is a large portion of people that follow SEC football more than Big XII football in that area.