All the weird words for military purposes especially relating to officer ranks come from french. You can blame the Normans (and by extension once again everything is scandavia’s fault) or that whole time period where England and France were basically constantly at war, or once again everything is Napoleon’s fault.

France had a long period as the dominant land power of Europe and that resulted in a lot of military organization words in most European languages being pulled from them. It’s similar to how a lot of military traditions and styles come from Prussia.