It falls into a category that is apparently called “Grand Strategy” games. Basically, you pick a territory to control starting in November of 1444. Then you (micro) manage the army and navy, trade, diplomacy, missionaries, production and expansion for each territory, handle local uprisings and events (like a stupid civil war that ended my game as Castille after successfully annexing Grenada).
I’m terrible at these games, but love them and can’t seem to stay away. Anyone else tried it?