spheres of influence

Spheres of influence are regions or domains where a nation, organization, or powerful entity exercises dominant control or sway, even without formal authority.

The term originated in imperial diplomacy, where great powers carved up territories: China was divided into European spheres of influence in the 19th century.

Now it applies to any arena where one party holds outsized sway: The company expanded its sphere of influence into Asian markets.

The plural often describes competing zones of control: The Cold War divided Europe into American and Soviet spheres of influence.