Territorial integrity

Territorial integrity is the principle under international law that nation-states should not attempt to promote secessionist movements or to promote border changes in other nation-states. Conversely it states that imposition by force of a border change is an act of aggression.

In recent years there has been tension between this principle and the concept of humanitarian intervention under Article 73.b of the United Nations Charter "to develop self-government, to take due account of the political aspirations of the peoples, and to assist them in the progressive development of their free political institutions, according to the particular circumstances of each territory and its peoples and their varying stages of advancement."

As far back as the earliest written records, there have been political units claiming a definite territory. Intrusion into these territories was considered an act of war, and normally resulted in combat. There were also sometimes several layers of authority, with units waging war on each other while both recognising some higher authority. Ancient and medieval nobility would fight private wars amongst while still acknowledging the same king or emperor, such as was case in the Spring and Autumn period in ancient China, when the Eastern Zhou Dynasty were nominal rulers. Catholic monarchs would often fight one another while recognizing the ecclesiastical authority of the same Pope.

Supporters of concept of Westphalian sovereignty consider that the modern idea of territorial integrity began with the Peace of Westphalia in 1648. This is disputed.

The League of Nations was intended to uphold territorial integrity and other principles of international law. It did condemn the Italian invasion of Ethiopia. It broadly supported the Chinese Republic over the creation of Manchukuo in Manchuria and eastern Inner Mongolia. Most historians say that the League was discredited by its failure to make these judgements effective.

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Wikipedia