Nation-state

A nation-state is a specific form of state (a political entity), which exists to provide a sovereign territory for a particular nation (a cultural entity), and which derives its legitimacy from that function. It is defined as a sovereign state of which most of the citizens or subjects are united also by factors which define a nation, such as language or common descent. It is almost by definition a sovereign state, meaning that there is no external authority above the state itself. The nation-state implies the parallel occurrence of a state and a nation.

The United Federation of Planets requires that planets have a unified government in order to be considered for Federation membership. However, planetary citizens often feel an attachment to their native region, which may have previously been a nation-state.