In late 1917, the German High Command was desperate to knock Russia out of World War I and devote more resources to the Western Front. Despite upheaval at all levels of society and especially within the military, Russia had remained a belligerent after the Russian Revolution in February 1917. The Russian military had essentially ceased to be an effective fighting force and yet the Provisional Government under Alexander Kerensky insisted on continuing the fight against Germany and Austria-Hungary. Thus the Germans devised a plan to invade a trio of islands in what is now Estonia. The operation would achieve two significant objectives and potentially force Russia to withdraw from the war. First, the Russian Baltic Fleet would be all but neutered by German control of the islands and, more importantly, the Russian capital of St. Petersburg would be threatened with invasion.
Dubbed Operation Albion, the plan called for a combined arms operation in which infantry and cyclist troops would land on October 12, 1917 on Saaremaa Island and isolate the garrison. Meanwhile, a naval task force would provide fire support and deal with any attempted intervention by the Russian Navy. Both land and sea forces would be supported by seaplanes which flew reconnaissance and bombing missions.
The Russians had formidable coastal batteries and garrisons on Saaremaa and nearby Muhn Island, however, a combination of poor morale and bold action by the German forces negated any Russian advantages. Russian morale was so low that some coastal batteries refused to engage the German ships in the hope that non-resistance would spare their batteries hostile fire. Russian forces were also hampered by poor communication and a lack of initiative by some commanders.
The German landings were achieved without serious opposition and cyclist troops quickly pushed to divide the Russian forces by occupying a dam which connected Saaremaa and Muhn. The cyclists reached their objectives and wreaked havoc on the Russian forces as they attempted to withdraw across the dam. Russian naval forces and 3 Royal Navy submarines attempted to intervene, however, their efforts were unsuccessful and resulted in the loss of the pre-dreadnought Slava, the destroyer Grom and a few smaller vessels. Apart from damage from mines, the Germans lost no capital ships during the operation.
After little more than a week, the Germans had secured the three islands – Saaremaa, Muhu and Hiiumaa and captured 20,000 Russian troops. Most significantly, though, the Germans had successfully launched a combined air-land-sea operation and were now poised to invade St. Petersburg. Less than 6 weeks after the action, the Russians sued for peace and German troops were freed from the Eastern Front to launch a last ditch effort to win on the Western Front.
The operation also had a minor World War II connection. Lieutenant Ernst Lindemann, later the captain of the ill-fated Nazi battleship Bismarck, served in the operation as a wireless officer aboard the battleship SMS Bayern. In 1944, the Soviets would launch their own Operation Albion, this time to wrest control of the islands from Nazi forces garrisoned there.