The idea of a nation state was and is associated with the rise of the modern system of states, often called the "Westphalian system" in reference to the Treaty of Westphalia (1648). The balance of power, which characterized that system, depended on its effectiveness upon clearly defined, centrally controlled, independent entities, whether empires or nation states, which recognize each other's sovereignty and territory. The Westphalian system did not create the nation state, but the nation state meets the criteria for its component states (by assuming that there is no disputed territory).