Alliance, Treaty of

Alliance, Treaty of 

a treaty between two or more states by virtue of which the signatories pledge to act in concert to maintain a certain political status quo and even to render mutual assistance in the event of war. The casus foederis, an event that invokes a treaty obligation to provide assistance, is usually stated precisely in the treaty itself.

The treaty of alliance, along with the peace treaty, is the oldest form of international pact. Treaties of alliance, both offensive and defensive, were concluded by states in the ancient Orient, Egypt, and India and subsequently in Greece and Rome.

In modern international law, offensive treaties of alliance are considered aggressive and therefore legally invalid. The UN Charter recognizes as rightful only defensive treaties of alliance, including treaties (pacts) of mutual assistance, invoked when a signatory is attacked by a third state. The USSR repeatedly took the initiative in signing such pacts even before World War II—for example, the treaty of alliance concluded with France on May 2, 1935, and the treaty concluded with Czechoslovakia on May 16, 1935. After World War II, the socialist countries signed more than 30 bilateral treaties of friendship, cooperation, and mutual assistance. The USSR has concluded treaties of friendship, cooperation, and mutual assistance with the German Democratic Republic (1964), Poland (1965), Mongolia (1966), Bulgaria (1967), Hungary (1967), Rumania (1970), Czechoslovakia (1970), and other countries. The Warsaw Pact of 1955 is also a treaty of alliance.