I've observed a few things while watching Moulin Rouge! that point to a rather old setting, e.g. the lamp beside Christian and also that Christian is using an old typewriter.
However, in the movie, I can hear modern music, e.g. the Indian song Chamma Chamma from the 1998 movie China Gate is used during the Evil Maharaja stage play.
I was confused with the timeline: an old lamp, an old typewriter, and a 1998 movie song.
In what year is the action of Moulin Rouge! taking place and what explains those contradictions?