From the first image--a nameless "Sergeant" and "Recruiting Officer" freezing in a field--Brecht's play sets its focus firmly on the lower classes affected by wars. No historically significant figures (General Tilly or the Kaiser, for example) make appearances in the play, being mentioned only in passing. Mother Courage, her family, and her companions are all the "little people," and it is their story which Brecht finds interesting. They usually are unable to extract any benefit from the war. Notice, too, how often minor characters in the play are given only a profession or a description rather than a proper name: we have peasants, numerous soldiers, generals, clerks, captains, officers, and even chaplains. This is not just because they are stock characters.
Key scenes to analyze in writing about this theme: Scenes 1, 5, 11, and 12.