Legal successor

Succession of states is a theory and practice in international relations regarding successor states. A successor state is a sovereign state over a territory and populace which was previously under the sovereignty of another state. The theory has its root in 19th century diplomacy. A successor state often acquires a new international legal personality, which is distinct from a continuing state, also known as a continuator, which despite change to its borders retains the same legal personality and possess all its existing rights and obligations (such as a rump state).

A state succession can be characterized as either being universal or partial. A universal state succession occurs when one state is completely extinguished and its sovereignty is replaced by that of one or more successor states. A partial state succession occurs when the state continues to exist after it has lost control of a part of its territory.

An example of a partial state succession is the case of the split of Bangladesh from Pakistan, there was no challenge to Pakistan's claim to continue to exist and to retain its membership of the United Nations: it was a continuator and not a successor. Bangladesh eventually was recognised as a new state: it was a successor and had to apply for UN membership.

An example of a universal state succession is the dissolution of Czechoslovakia. Neither part claimed any continuity: both the Czech Republic and Slovakia were new successor states.

Consequent upon the acquisition of international personality, the difficult matter of succession to treaty rights and obligations arises. Succession may refer to the transfer of rights, obligations, and/or property from a previously well-established prior state (the predecessor state) to the new one (the successor state). Transfer of rights, obligations, and property can include overseas assets (embassies, monetary reserves, museum artifacts), participation in treaties, membership in international organizations, and debts. Often a state chooses piecemeal whether or not it wants to be considered the successor state.

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