This video doesn't present its material in the most organized way, but I learned some facinating things about language, music, and their interaction within cultures from it.
First, some cultures don't even use their native languages as lyrics for songs. They have syllables that would mean nonsense in the language, but put to melody, they have meaning.
Second, songs written in one language generally don't translate well to another because of differences in emphasis and syllable count. This is why the high pieces of musical art in operas aren't translated; it just wouldn't be the same song if translated.