Which theory proposes the idea that the state comes into being when a small group of people takes over a territory and requires others to obey its rules?

hello,

i'm not so sure but i hope this in anyway.

the president of russia is head of state, and of a multi-party system with executive power exercised by the government, headed by the prime minister, who is appointed by the president with the parliament's approval.

hope this : )

what are the issues?