control, dominion, sway.
A political unit, typically having an extensive territory or comprising a number of territories or nations (especially one comprising one or more kingdoms) and ruled by a single supreme authority.
An expansive and powerful enterprise under the control of one person or group.
A political unit ruled by an emperor or empress.
The group of states or other territories that owe allegiance to an imperial power (foreign to them), when distinguished from the native territory of that power; imperial possessions.
The realm of overlords.
The position or quality of being an overlord.