You could have a look at the actual competition: http://www.c3l6.org/downloads
(I am an alumnus
) There is no historical component, it's very good as an entry-level Olympiad though definitely easier than the other Olympiads (for one thing, it's a first round, and also, it's for one-year-younger students).
If you mean the Monthly challenge, yeah I wouldn't have a clue. It seems mostly like chemical general knowledge (mixed with quick research skills).