in international law, the transfer of rights and duties from one state to another in connection with the transfer of territory or related events, such as the emergence of a new state, the merger of one state with another, the partition of a state, or secession. Contemporary international law recognizes state succession only for lawful territorial changes. In accordance with the principle of nonintervention, domestic state relations are not an object of state succession. State succession does not involve state boundaries: the treaties that established the boundaries and the status of the boundaries preserve their legal force with respect to the successor state.
Questions of state succession are particularly important because a large number of newly independent states have arisen in Asia, Africa, and Latin America with the collapse of imperialism’s colonial system. International law stipulates that these states are not obliged to recognize any treaties that were in effect on their territory at an earlier time. In cases where the successor state was formerly part of a sovereign state, the problem of state succession is to be resolved in accordance with the principle of the continuity of treaties. In such an instance, the only treaties annulled are those whose subject and goals are incompatible with the conditions created by state succession. When part of a territory is transferred from one state to another the principle of “mobility of treaty borders” applies: in the territory being transferred the treaties of the state under whose rule it has come begin to take effect.
The question of state succession is very important when a social revolution has occurred. Thus, the Soviet state reviewed the treaties concluded by Russia before the October Revolution of 1917 in conformity with the principle advanced by V. I. Lenin at the second All-Russian Congress of Soviets: reject all the treaties of former tsarist Russia that gave foreign states an opportunity to plunder the country and recognize the treaties that established good neighbor relations. The Soviet state annulled Russia’s secret annexation treaties, its unequal treaties with Oriental countries, and the loans obtained by the tsarist and Provisional governments in the interest of the classes overthrown by the revolution. This action by the Soviet state promoted the establishment of new, democratic principles in international law.