Your mention of Louisville, USA without the state made me realize just how chaotic the US is in many ways. Because many parts of the US were settled by people relocating from more eastern towns or from European roots, they tended to name their new cities in memory of their old. Additionally, there are >20,000 cities and so the plausible set of names sort of runs out.
So many cities have the same names as others.
I thought this illustration of the 10 most popular city names in the US might be interesting to someone from an older, perhaps more well-organized, country.
I live in Columbia, and there are at least 6 or 7 of them around.