London Straits Convention

In the London Straits Convention concluded on 13 July 1841 between the Great Powers of Europe at the time – Russia, the United Kingdom, France, Austria and Prussia – the "ancient rule" of the Ottoman Empire was re-established by closing the Turkish Straits (the Bosporus and Dardanelles), which link the Black Sea to the Mediterranean, from all warships whatsoever, barring those of the Sultan's allies during wartime. It thus benefited British naval power at the expense of Russia as the latter lacked direct access for its navy to the Mediterranean.

The treaty is one in a series dealing with access to the Bosporus, the Sea of Marmara, and the Dardanelles. It evolved as a reaction to the secret article in the Treaty of Hünkâr İskelesi (Unkiar Skelessi), created in 1833, in which the Ottoman Empire guaranteed exclusive use of the straits to Ottoman and Imperial Russian warships in the case of a general war, allowing no 'foreign vessels of war to enter therein under any pretext whatsoever'. The modern treaty controlling relations is the Montreux Convention Regarding the Regime of the Straits from 1936, which is still in force.

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