There are many more such regions in Poland, for example - I have no time at the moment to look up their translations, but we have, among others: Mazowsze, Slask, Pomorze, Lubelszczyzna, Warmia i Mazury. That's five, too. And each of these regions has noted differences in: dialect (to the point of using language completely incomprehensible to others, which at least three(!) of this regions do), culture, food, general behavior, economy, and quality of life.

These differences between regions inside one country is exactly what is comparable to differences between Midwest and Northeast.

Now think about the fact that Europe consists of tens of countries, many of which are significantly more diverse internally than Poland. And try to compare this monstrous complexity to differences between USA regions.

For me it seems to be daunting and impossible task because of huge difference in scale, yet you have no problem with it. I can only admire your courage :)