Chevaliers??

I think it is fictitious. "Chevaliers" means "Knights" I believe the organization in the movie is Chevaliers du Saint Marie meaning the Knights of St. Mary. It would be a common enough name for a religious organization so there may be several out there. Therefore, please don't go about thinking or worse, accusing them of being Nazi collaborators.

It never was explained and may just be a made up organization. The title "chevalier" is real however, and connotes as low ranking noble in the old French aristocracy.

-- If Ewan McGregor were a lollipop I'd be a diabetic strumpet --

Some kind of Christian sect, it seemed like. Probably fictional, made up for the movie.

The people, and the people alone, are the motive force in the making of history.
-Mao Zedong

It was the society of all the illegitimate children of Maurice Chevalier. THere were hundreds of them all over France and the colonies!!

The Milice by another name.