Battle of Gotland

2 July 1915, Off Gotland, Baltic

Russian victory

Russian codebreakers read German signals about a minelaying sortie. Rear Admiral Bakhirev's cruisers caught the minelayer Albatross and her escorts in fog off Gotland; Albatross was set on fire and ran aground on the neutral Swedish coast. German cruisers came up and both sides broke off, short of ammunition, and the British submarine E9 torpedoed Prinz Adalbert. It is often called the first naval action decided by signals intelligence. (19 June in the Russian Old Style calendar.)