The Dardanelles in the First World War

The Dardanelles, a narrow strait between the Gallipoli peninsula and the Asian shore of the Ottoman Empire, were the only passage from the Black Sea to the Mediterranean. In 1914 they were also the only practicable sea route by which Russia could keep in touch with its western allies. From the autumn of 1914 mines and forts kept the strait closed. In 1915 the Entente tried to open it, first with the fleet and then with a landing at Gallipoli, and was defeated. The Allied fleet passed through it only after the armistice of 1918.

The gate closed (1914)

The strait is about 60 kilometres long and, at its narrowest point, the Narrows at Çanakkale, little more than a kilometre wide. Forts guarded its shores, and even before war was declared there were mines in the strait, through which Turkish pilots guided ships. In August 1914 the German warships Goeben and Breslau, fleeing the British fleet, took refuge there. The war minister, Enver Pasha, allowed it, and the Ottoman government later announced that it had bought both ships.

At the end of September the British squadron watching the mouth of the Dardanelles turned back a Turkish torpedo boat with German sailors on board. The German commander of the fortifications, Erich Weber, known as Weber Pasha, then had the strait closed without consulting the government. Mines and nets were laid, the lighthouses were put out and signs forbidding passage were put up. The American ambassador in Constantinople, Henry Morgenthau, dated the closure to 27 September 1914. He wrote that almost all of Russia’s trade had gone this way, and that Russia was left only with the ice-bound ports of Archangel and Vladivostok.

When on 29 October a fleet under German command shelled Russian ports, Turkey was at war. On 3 November British and French ships shelled the forts at the mouth of the strait, and a magazine explosion wrecked the fort of Sedd el Bahr. The bombardment, however, served mostly as a warning to the Turks, who began to strengthen a defence built on minefields and batteries. On 13 December the British submarine B11 passed under five lines of mines and torpedoed the old battleship Mesudiye.

The attack on the strait (1915)

The idea of opening the straits gave the First Lord of the Admiralty, Winston Churchill, no peace. On 13 January 1915 the War Council ordered an expedition to be prepared. The naval operation began on 19 February with the bombardment of the forts at the entrance and ended on 18 March, when the fleet lost three battleships on mines. In the same weeks Russia demanded its allies’ consent to its annexing Constantinople and the straits after the war.

Since the fleet had failed, the army was to take the shores. On 25 April British, Australian, New Zealand and French soldiers landed on the Gallipoli peninsula and at Kum Kale. Through the eight months of the Gallipoli campaign the Turks of Otto Liman von Sanders and Mustafa Kemal did not give up the heights commanding the Narrows. In May the German submarine U-21 sank two battleships, so the heavy ships were withdrawn to Mudros bay on Lemnos.

Under water the strait proved passable. Early on 25 April the Australian submarine AE2 became the first to get past the minefields and batteries and reach the Sea of Marmara. Five days later a Turkish torpedo boat caught her, but British submarines followed. Martin Nasmith’s E11 torpedoed a ship in the harbour of Constantinople, in August sank the battleship Barbaros Hayreddin, and in three patrols sent more than 80 ships and smaller vessels to the bottom. This hampered the Turks in bringing troops to the peninsula by sea.

In December 1915 and January 1916 the Allies secretly evacuated the peninsula. The strait stayed in Turkish hands, and the campaign cost the two sides together about half a million killed, wounded and sick.

Guarding the mouth (1916–1918)

The British kept watch on the mouth of the Dardanelles. Monitors lay at anchor off the island of Imbros, and extensive minefields were laid between the island and the Gallipoli peninsula. The Goeben and the Breslau meanwhile spent more than three years fighting mainly the Russians in the Black Sea. When the war in that sea died down after the October Revolution, the Germans decided to use them in the Aegean.

On 20 January 1918, in the Battle of Imbros, the two ships sank two British monitors but then ran into a minefield. The Breslau sank, and the Goeben ran aground off Cape Nagara, near the narrowest point of the strait. For almost a week British aircraft bombed her, but on 26 January she was pulled off the shoal. The British submarine E14, sent to torpedo her, no longer found her there and was sunk on the way back.

Opening (1918)

The opening of the straits was the first of the terms that the British Vice-Admiral Somerset Gough-Calthorpe had to obtain at all costs. The armistice signed at Mudros on 30 October 1918 bound Turkey to open the Dardanelles and the Bosporus, hand the forts over to the Allies and help remove the mines. Once minesweepers had cleared a passage, on 12 November the Allied fleet passed through the strait it had failed to force in 1915, and the next day it anchored off Constantinople. According to various sources it numbered from about 50 to more than 60 warships.

Constantinople remained under Allied occupation until 1923. The Treaty of Lausanne concluded that year restored the strait to Turkey, on condition that its shores remain demilitarised and that the warships and merchant ships of all nations could pass through it freely.