Munchen or Munich?

I don't get it. There, I said it.

If you ask me, a name is a name is a name...in any language.

I get that the pronounciation of a name could be different from the perspective of the speaker. For example, my name, Tim, could be prounounced "Teem" by a native Spanish speaker. That makes sense to me. But, seriously, tell me this:

Why is London, the real name, the actual name of the City, called Londres by Spanish speakers? Why is Munchen, the real name of the City, called Munich by English speakers?

Hamburg is Hamburg to Germans, and it's Hamburg to English speakers. Madrid is Madrid across the globe. Barcelona is Barcelona to anyone and everyone, but Sevilla is Seville to English speakers. Lisbon, the capital city of Portugal? It's real name is Lisboa.

What gives?

I get that New York is Nueva York to Spanish speakers - the word "new" is translatable.

But, London? Londres?

Munchen? Munich?

I just don't get it.

A name is a name is a name.