Blockade of Germany
Part of World War I
Atlantic naval campaign
Mediterranean naval campaign
Date 1914–1916
Location Atlantic Ocean, Mediterranean Sea
Result Inconclusive
Allied Powers:
Flag of the United Kingdom United Kingdom
Flag of Italy (1861-1946) crowned Italy
Flag of France France
Central Powers:
Flag of the German Empire Germany

Flag of Austria-Hungary (1869-1918) Austria-Hungary
Flag of the Ottoman Empire Ottoman Empire

The Blockade of Germany, or the Blockade of Europe, occurred from 1914 to 1917. It was a prolonged naval operation conducted by the Allied Powers during World War I in an effort to restrict the maritime supply of raw materials and foodstuffs to the Central Powers, which included Germany, Austria-Hungary and Turkey. The German Board of Public Health in December 1918 claimed that 381,500 German civilians died from starvation and disease caused by the blockade up until the end of December 1918. An academic study done in 1928 put the death toll at 212,000.

Both the German Empire and Great Britain relied heavily on imports to feed their population and supply their war industry. Imports of foodstuffs and war material of all European belligerents came primarily from the Americas and had to be shipped across the Atlantic Ocean, thus Britain and Germany both aimed to blockade each other. The British had the Royal Navy which was superior in numbers and could operate throughout the British Empire, while the German Kaiserliche Marine surface fleet was mainly restricted to the German Bight, and used commerce raiders and unrestricted submarine warfare to operate elsewhere.



Prior to World War I, a series of conferences were held at Whitehall in 1905–1906 concerning military cooperation with France in the event of a war with Germany. The Director of Naval IntelligenceCharles Ottley—asserted that two of the Royal Navy′s functions in such a war would be the capture of German commercial shipping and the blockade of German ports. A blockade was considered useful for two reasons: it could force the enemy′s fleet to fight and it could also act as an economic weapon to destroy German commerce. It was not until 1908, however, that a blockade of Germany formally appeared in the Navy′s war plans and even then some officials were divided over how feasible it was. The plans remained in a state of constant change and revision until 1914, the Navy undecided over how best to operate such a blockade.


The British—with their overwhelming sea power—established a naval blockade of Germany immediately on the outbreak of war in August 1914, issuing a comprehensive list of contraband that all but prohibited American trade with the Central powers, and in early November 1914 declared the North Sea to be a War Zone, with any ships entering the North Sea doing so at their own risk. The blockade was unusually restrictive in that even foodstuffs were considered "contraband of war". There were complaints about breaches of international law, however most neutral merchant vessels agreed to dock at British ports to be inspected and then escorted—less any "illegal" cargo destined for Germany—through the British minefields to their destinations.

The Northern Patrol and Dover Patrol closed off access to the North Sea and the English Channel respectively.

The Germans regarded this as a blatant attempt to starve the German people into submission and wanted to retaliate in kind.

The blockade also had a detrimental effect on the U.S. economy. Under pressure especially from commercial interests wishing to profit from wartime trade with both sides, the U.S. government protested vigorously. Britain did not wish to antagonize the U.S., but cutting off trade to the enemy seemed a more pressing goal. Eventually, Germany′s submarine campaign and the subsequent sinking of the RMS Lusitania and other civilian vessels with Americans on board did far more to antagonize U.S. opinion than the blockade had.

A memorandum to the British War Cabinet on 1 January 1917,(the blockade became less effective after the Action of 19 August 1916), stated that very few supplies were reaching Germany or its allies either via the North Sea or other areas such as Austria′s Adriatic ports (which had been subject to a French blockade since 1914). The blockade was effectively broken after the Battle of Jutland in June 1916. The resulting withdrawl of the British Grand Fleet caused it to remain in port for the remainder of the war in the event of a German attack on the British homeland itself.