Of these there are many, Barons, Dukes, Kings, Emperors, Chieftains, Warlords, Bankers and Mafias.
A long these many divert some of their attention into other realm spheres, Crusader states, Grand trade domains(think Patricians of Venice), Sorcerer Tyrants, Clan lords( who decree not only the rules of their domain, but the values of their society and kin as well)
In the realm of any organized religion.
Temples, Cults, Druids.
The art of the Deal, the hunt for profit, the Guilds, The caravan lords, the Grand Admiral of grand trade fleets, Corporations, and the Grand Trade Companies of Earth history.
The reclusive Wizard, the Lich, Academies of learning and exploration.
The Bardic guild, the renowned monks, The Game masters of the great Colosseum, the painters of virtue and vice, the theater guild, the opera halls, the Olympic games.
These are but a few, what would you add?
And which realm will you be interested in playing next?