le roi convoqua le ban et l'arrière-ban

Le ban were the king’s direct vassals, such as earls, barons, and knights; l’arrière-ban were the king’s indirect vassals, or the vassals of vassals. “A proclamation whereby all (except some privileged officers and citizens) that hold their lands of the Crowne, are summoned to meet at a certaine place, there to attend the King whithersoever and against whomsoever he goes.”—Cotgrave.