suzerain state
A state that exercises political control over a dependent state, especially in historical contexts such as tributary systems or colonial relationships.
The Qing dynasty claimed suzerainty over neighboring countries.
Relationships between suzerain states and vassal states have existed in various forms throughout history.
Compound of 宗主 (suzerain) and 国 (country). The term is used in historical and political contexts to describe a dominant state in a suzerain–vassal relationship.