Non-commissioned rank
In France, and many countries whose forces were structured in the method used in France, some branches of the army and the gendarmerie use brigadier for a rank equivalent to caporal (Corporal), and brigadier-chef for a rank equivalent to caporal-chef. Brigadier is used by arms of the army which are by tradition considered "mounted" arms such as logistics or cavalry units. A similar usage exists elsewhere, e.g. in Italy.
This usages derive from the use of "brigade" to denote a squad or team of cavalrymen, similar to the occasional English civilian usage "work brigade".
In the French gendamerie, the brigadier ranks are used as in the army, i.e. as junior enlisted ranks (gradés), while the French police use brigadier ranks as their sub-officer (sous-officier) ranks. Since all professional police and gendarmes have sub-officer status, the gendarmerie brigadier ranks are rarely used, since they are used only by auxiliaries. On the other hand the police brigadier ranks, used by the professional police, are common.