Maître de camp (French - master of the camp) was a rank in the Ancien Régime French army equivalent to Colonel. A maître de camp commanded a regiment. A regiment's commander was initially called a Colonel from the time of Francis I to that of Henry II, then a Mestre de camp from then until 1661, after which the name of the rank was repeatedly changed. Colonel was used whenever the rank of Colonel General (ie commander in chief of all the regiments in an army) was out of use or suppressed. When "colonel general" was revived, so was "colonel" or "maître de camp".

The rank of Maître de camp général also existed, equivalent to Colonel General.

Source

• Julian Corbett, The Colonel and his Command, The American Historical Review, Vol. 2, No. 1. (Oct., 1896), pp. 6-7]