hegemony

Leadership or dominance, esp. by one country or social group over others.

That unity had dissipated as the Oldtime Weyrleaders had reasserted their traditional domination over the Holds bound to their Weyr for protection, and a grateful Pern had ceded them those rights. But in four hundred Turns the interpretation of that old hegemony had altered, with neither party sure of the translation.

Definition from Dictionary.com