Black Sea Straits

the general name for the Bosporus, the Dardanelles, and the Sea of Marmara, which lies between the Bosporus and the Dardanelles (seeBOSPORUS and DARDANELLES). The Black Sea straits constitute the only passage between the Black and Mediterranean seas and consequently occupy a special place in the system of international waterways. So long as Byzantium and, after the Turkish conquest of Constantinople in 1453, the Ottoman Empire ruled the entire Black Sea region, the Black Sea was an internal sea and the use of the Black Sea straits, therefore, was the internal affair of the corresponding state. By the late 17th century, however, the situation was fundamentally different. Peter I embarked on the construction of the Azov Fleet, and in 1696 he took Azov. Russia’s border now extended to the Sea of Azov and the Black Sea. Consequently, entry into and departure from the Black Sea became an international issue and thereafter constituted an important part of the Eastern Question (seeEASTERN QUESTION). The efforts of Russian diplomats to secure access to the Black Sea and Black Sea straits for the Russian fleet long remained unsuccessful. In 1774 the Treaty of Kuchuk Kainarji recognized Russia’s right to commercial navigation in the Black Sea and Black Sea straits [seeKUCHUK KAINARJI, TREATY OF (1774)]. Later, other states, except those at war with Turkey, were granted the same right.

The resolution of the question of the passage of warships proved a much more complex matter for Russian diplomacy. The security of the Black Sea countries necessitated the establishment of a regime of the straits that would guarantee the naval fleets of these countries reliable access to the high seas but at the same time provide protection from the threat of aggression from non-Black Sea powers. This principle was formulated clearly in 1802 by the chancellor A. R. Vorontsov in response to French claims regarding the right of passage of the French fleet through the Black Sea straits. At that time, Turkey held a position similar to Russia’s position. While prohibiting the passage of warships of non-Black Sea countries, Turkey granted Russian warships, following the Russo-Turkish treaties of alliance of 1799 and 1805, the right to pass into the Mediterranean Sea (seeRUSSO-TURKISH TREATIES OF ALLIANCE).

Meanwhile, the non-Black Sea powers, first and foremost Great Britain and France, were seeking to obtain the right of direct access to the Black Sea for both their commercial vessels and their warships, while at the same time denying that right to the Russian fleet. Inasmuch as there could be no straightforward justification for such an unjust demand, they sought “parity” with Russia, that is, either opening up or closing completely the Black Sea straits to warships of all countries.

Under the influence of Napoleon’s diplomacy, Turkey in 1806, in violation of the 1805 treaty of alliance with Russia, revoked the right of free passage of Russian ships through the straits. Soon after, during the Russo-Turkish War of 1806–12, Great Britain imposed a treaty on Turkey (1809) that, under the guise of an “ancient rule of the Ottoman Empire,” prohibited the passage of the warships of any foreign power through the Black Sea straits. The Treaty of Unkiar Skelessi of 1833, virtually restoring the Russo-Turkish alliance, obligated Turkey to close the Dardanelles on Russia’s demand to warships of other countries [seeUNKIAR SKELESSI, TREATY OF (1833)]. However, a few years later, the London Convention of 1840 resurrected the supposedly always extant ancient rule of the Ottoman Empire.

The first multilateral international agreement concerning the Black Sea straits, the London Convention of 1841, confirmed the ancient rule and transformed it into an international obligation. Turkey and Russia thus lost the right of independently regulating the passage of warships into and from the Black Sea through bilateral agreements. The Russian fleet found itself locked within the Black Sea. The prohibition of passage for warships of non-Black Sea countries was of little value to Russia, especially since the 1841 convention stipulated that the ban applied only in peacetime. Turkey, meanwhile, fell ever more under the influence of the Western European powers and often made exceptions to the ancient rule for them. This was one of the leading factors that led tsarist Russia into war with Turkey in 1853 (seeCRIMEAN WAR OF 1853–56). The Paris Peace Treaty of 1856, which ended the war, prohibited Russia, under the guise of an obligation to maintain the “neutralization” of the Black Sea, from taking effective steps to protect its Black Sea coast [seePARÍS, TREATY OF (1856)]. In 1870 the Russian government refused to recognize the articles in the Treaty of Paris concerning the “neutralization” of the Black Sea. The London Convention of 1871 sanctioned the abolition of these articles but essentially retained the same status of the Black Sea straits as the 1841 convention. The status was also preserved by the Berlin Treaty of 1878 (seeBERLIN CONGRESS OF 1878).

Right up to World War I, Russian diplomacy sought in vain to alter the status of the Black Sea straits, which was unfavorable to Russia. There were cases, in 1891 and 1894, for example, when the Turkish sultan allowed Russian warships to pass through the Bosporus and the Dardanelles, albeit without armament and without armed escort, but the non-Black Sea powers made it difficult to obtain such authorization, and during the Russo-Japanese War of 1904–05 Great Britain staged a naval demonstration near the Dardanelles to prevent Russian warships from passing into the Mediterranean and appearing in the Far East.

International supervision of the Black Sea straits was also disadvantageous for Turkey, since it infringed on Turkey’s sovereignty, tended to turn Turkey into a semicolony of the imperialist powers, and led to a dangerous exacerbation of relations with Russia. In the late 19th and early 20th centuries, Great Britain and France enjoyed the greatest economic and political influence in Turkey. However, in the years immediately preceding World War I, German influence increased significantly.

After Turkey’s entry into World War I as a German ally, the secret Anglo-French-Russian Agreement of 1915 was signed, providing for the inclusion of Constantinople (Istanbul) and the Black Sea straits within the Russian Empire. This agreement was expected to maintain the interests of Russian ruling circles in continuing the war with Germany until a victorious conclusion. (SeeANGLO-FRENCH-RUSSIAN AGREEMENT OF 1915.)

After the victory of the Great October Socialist Revolution, Soviet Russia renounced the secret treaties of the tsarist government and the agreement on Constantinople and the Black Sea straits. The imperialist powers, on the other hand, set themselves the task of seizing the Black Sea straits. After the signing of the Moudhros Armistice of 1918, the navy of the Entente powers entered the Black Sea straits (see MOUDHROS ARMISTICE OF 1918). In 1920 the troops of the Entente occupied Istanbul. Their control of Istanbul and the Black Sea straits zone enabled the imperialist powers to organize an armed intervention into southern Soviet Russia, as well as into Turkey, with the help of the Greek Army. According to the Treaty of Sevres of 1920, signed by the sultan’s government, the issue of the Black Sea straits was resolved to the benefit of the imperialist powers [see SEVRES, TREATY OF (1920)].

The Treaty of Sevres never went into effect owing to the failure of the Anglo-Greek intervention in Turkey. V. I. Lenin worked out the principles for the resolution of the straits question that met the interests of both Soviet Russia and Turkey. They were set down in the Moscow Treaty of Mar. 16, 1921, between the RSFSR and Turkey, which envisioned that the international status of the Black Sea and Black Sea straits would be worked out by a conference “of delegates from the countries with a Black Sea coastline on the condition that the decisions reached not infringe on the complete sovereignty of Turkey or the security of Turkey and its capital Constantinople.” Identical articles were included in the Treaty of Kars of 1921 and a Ukrainian-Turkish treaty of 1922 [seeKARS, TREATY OF (1921)]. At the Lausanne Conference of 1922–23, the Soviet delegation worked hard to obtain a just resolution of the straits question (seeLAUSANNE CONFERENCE OF 1922–23). The Lausanne convention on the straits, signed on July 24, 1923, stipulated that the Black Sea straits zone would be demilitarized and opened to passage by any warships. Because such a regime would subject the Black Sea countries to the threat of aggression, the Soviet Union refused to ratify the convention. In April 1936 the Turkish government, relying on the support of Great Britain, which sought to draw Turkey into the orbit of its Mediterranean Sea policy and to make use of Turkish naval bases, proposed that the powers that met in the Lausanne Conference conduct negotiations for a new convention on the Black Sea straits.

An international conference on the straits question opened in Montreux in June 1936; it ended on July 20, 1936, with the signing of a new convention on the Black Sea straits (seeMONTREUX CONFERENCE OF 1936). This convention took into account, although not fully, the interests of the Black Sea countries. All ships of the Black Sea states were allowed to cross the Black Sea straits observing established rules of passage, whereas limitations on tonnage, class, and cruising time in the Black Sea were imposed on the warships of non-Black Sea powers. Passage by warships of countries at war was prohibited. Turkey had the right, in case of its entry into a war or being threatened by war, to permit or prohibit any warship to pass through the straits.

During World War II (1939–45), Turkey, declaring its neutrality after Germany attacked the USSR, nevertheless allowed the fascist aggressors to use the Black Sea straits for their purposes. In light of these circumstances, the Potsdam Conference of 1945 acknowledged that the convention concluded in Montreux would have to be revised (seePOTSDAM CONFERENCE OF 1945). In 1946 the USSR began negotiations with Turkey, but the Turkish government rejected Soviet proposals. In 1953 the Soviet government informed Turkey that it had revised its former view with respect to these proposals. Thus, the convention of 1936 remains the international document regulating navigation in the Black Sea straits.