If you are king, you may choose the culture, which changes both icons and troops. If you are not a king you may choose the icon for your party. Each faction has special parties’ icons changing with the amount of men in the party.
The flag of the ruler is the flag of every vassal (also for the player) Player can choose if to start the campaign as the really existed ruler of one of these nations The Pelopponnesian League and the Delian League. The war between Sparta and Athens involves almost all the greek city-states, split in two opposed alliances:
Sparta Mount & Blade: Warband mod | Released Jul 20, 2019