A conversation with Thomas Barfield (Boston University) about a distinctive category of empires that he has proposed in a new book, Shadow Empires: An Alternative Imperial History (Princeton University Press 2023). These are empire that derive a significant part of their revenues or symbolic capital not from lands that they rule directly but by extorting them from other empires, from control over trade routes, or from the ruins of previous states. During its long history, Romanía dealt with a number of these "exogenous" empires, including the Huns, Venetians, and Rus'.
