Even today, Europe is far more diverse than the US in the sense that culture doesn't travel far: traveling a few hours by train in any direction from where you

Even today, Europe is far more diverse than the US in the sense that culture doesn't travel far: traveling a few hours by train in any direction from where you were born could easily put you in a place where you don't speak the language and where cultural practices, while nominally Christian, were markedly different with regards to dates and times, things people ate, what counted as legitimate use of a public place and so on. The US is much more homogeneous than Europe with regards to these kinds of criterion, which in practice greatly impacts government administration. Switzerland is like this but turned up a notch -- an hour's travel by train is usually enough to land in areas with mutually incomprehensible spoken languages, even when they are both nominally German.