Oxom

Why should Assam be Oxom?
Can you pronounce the German names correctly? The Chinese ones? Why their spells did not become simplified in English? Where from the word "Assam" came? Why the strange 'x' remained or where did it came from in Assamese pronounciation?

I wish I did a PhD in Linguistics. Btw, here is an article which has summarized some interesting findings/observations in this direction and might answer some of the questions above.
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