Military logistics as "material" or "materiel"

I work on a U.S. defence installation which stores a great deal of supplies and logistics for the military. One thing I have noticed about many of the older employees on base is that they refer to military logistics as “materiel” , instead of the usual “material”. I wonder if this is some kind of French term, for military supplies, and if this used to be in common usage.

Not French, at least not exclusively. It was (and still is, among those of us fighting a losing battle to preserve the language) the preferred term. Why? Because “material” has lots of meanings in English, while “materiel” means military supplies, specifically end items such as tanks or rifles.