Formation of the International Legal Regime of the Caspian Sea

Abstract

This article presents a comprehensive analysis of the evolution of the international legal status of the Caspian Sea from the 9th century to the late 20th century, with an emphasis on bilateral relations between Russia (later the USSR) and Persia (Iran). The authors trace how early trade and military interactions between Slavic tribes and the population of Caspian territories developed into a systematic expansion of Russian influence in the 16th– 19th centuries, cemented by key treaties such as the Treaties of St. Petersburg (1723), Resht (1732), Ganja (1735), Gulistan (1813), and Turkmenchay (1828), which established rules of navigation, trade, and territorial concessions, as well as Russia's monopoly on the navy. In the period after 1917, Soviet policy led to the annulment of previous agreements and the conclusion of new treaties. The conventions of 1921, 1927, 1931, 1935, and 1940 confirmed the closed status of the Caspian Sea as a "Soviet-Iranian" body of water with restrictions on extra-regional powers. The study emphasizes the continuity of legal norms, the need to modernize the sea's status after the collapse of the USSR with the emergence of new littoral states (Azerbaijan, Kazakhstan, and Turkmenistan), and the role of multilateral mechanisms in achieving consensus on the Caspian Sea.