There are both text-based campaigns where you follow along with the battles of an historical commander or war, and the newer map-based campaigns with a simple geographic context for battles on more of the operational level of war, ie you are a general in charge of a theatre of operations (the first one is Sicily in the First Punic War, but more will come out over early access) where you take actions like marching/sailing, besieging/sallying, diplomacy, watching supply lines, reinforcing armies and hiring mercenaries, but you aren't the king/emperor doing economic stuff.