The border between the categories that compose today the hierarchical view of the Armed Force is different from that of three or four hundred years ago. In fact, it was not difficult that a "General Major Sergeant" was high-ranking respect to a Colonel.
Successive reforms assigned new meaning and task to the different ranks that were forming when the Armies, the Corps and the combat techniques got complicated. It was necessary to have a group of Officers and NCOs to lead a unit.
The codification of the hierarchical chain occurred between the 17th and the 18th century; also the Italian hierarchical chain refers to that codification. It had got French influences for the presence of French language Swiss Regiments, in addition to all the Piedmontese nobility.