The Westphalian system, also known as Westphalian sovereignty, is a principle in international law that each state has exclusive sovereignty over its territory. The principle developed in Europe after the Peace of Westphalia in 1648, based on the state theory of Jean Bodin and the natural law teachings of Hugo Grotius. It underlies the modern international system of sovereign states and is enshrined in the United Nations Charter, which states that "nothing ... shall authorize the United Nations to intervene in matters which are essentially within the domestic jurisdiction of any state."
The ratification of the Treaty of Münster, part of the Peace of Westphalia that ended the Thirty Years' War
International law is the set of rules, norms, and standards generally recognized as binding between states. It establishes norms for states across a broad range of domains, including war and diplomacy, economic relations, and human rights. International law differs from state-based domestic legal systems in that it is primarily, though not exclusively, applicable to states, rather than to individuals, and operates largely through consent, since there is no universally accepted authority to enforce it upon sovereign states. States may choose to not abide by international law, and even to breach a treaty but such violations, particularly of peremptory norms, can be met with disapproval by others and in some cases coercive action ranging from diplomatic and economic sanctions to war.
The Hittite version of the Treaty of Kadesh, among the earliest extant examples of an international agreement
A portrait of Dutch jurist Hugo Grotius
Justices of the International Court of Justice in 1979
The Peace Palace in the Hague, which houses the International Court of Justice
