Orkney was the site of a naval base at Scapa Flow, which played a major role in World War I. After the Armistice in 1918, the German High Seas Fleet was transferred in its entirety to Scapa Flow while a decision was to be made on its future; however, the German sailors opened the sea-cocks and scuttled all the ships. During World War I the 10th Cruiser Squadron was stationed at Swarbacks Minn in Shetland and during a single year from March 1917 more than 4,500 ships sailed from Lerwick as part of an escorted convoy system. In total, Shetland lost more than 500 men, a higher proportion than any other part of Britain, and there were waves of emigration in the 1920s and 1930s.