On the night of 13 August 1914, one of the best German cruisers, Magdeburg, ran aground in the fog on the reefs off Odensholm Island. The Russian sailors from the Pallada and Bogatyr captured the Magdeburg's commander and 56 crewmen. The most valuable items confiscated were signal logs and code tables that were later used for decoding radio transmissions throughout the entire war.
In late September, at the mouth of the Gulf of Finland, the German submarine U-26 torpedoed the cruiser Pallada. The explosion detonated the ship's ammunition, and within a few minutes the cruiser disappeared into the water along with all 597 crewmembers. Following the tragedy of the Pallada, Admiral Essen ordered that all ships be escorted by destroyers. Furthermore, he ordered the shifting of operations to the southern area of the Baltic, closer to the German sea lanes. Under Admirals Ludvig Kerber, Viktor Kanin, Captain Alexander Kolchak and others, the detachments of cruisers and torpedo boats laid 1,500 mines in enemy waters. Germany's armoured cruiser Friedrich Karl, four mine-sweepers, and fifteen steamships were subsequently destroyed and the cruisers Augsburg and Gazelle seriously damaged.
In the spring of 1915, the commander of the Baltic Fleet, Admiral Essen, died of pneumonia. Vice-Admiral Kanin, who replaced him, expanded the zone of the fleet's operations, strengthened the defences at Aland and Moonsund Islands, and took control of the Gulf of Riga. The German U-26 sank the mine-layer Yenisei, but three months later she herself struck Russian mines and sank in the Baltic.
Organized by Signal Officer-in-Chief Adrian Nepenin and Commander Ivan Rengarten, radio intelligence proved invaluable to Russian seamen in the Baltic; by using it Rear Admiral Mikhail Bakhirev and his cruiser brigade managed to intercept the German detachment of Commodore Karf on 19 July 1915, as it returned from planting mines off Gotland Island. In the ensuing battle the cruisers Admiral Makarov, Boyan, Bogatyr and Oleg sent the crui-ser Augsburg into retreat and forced the dama-ged mine cruiser Albatross to run aground. Under Captain Alexander Pyshnov, the cruiser Ryurik severely damaged the German cruiser Rhoone, forcing it to withdraw.
In late July 1915, the situation in the Baltic Sea changed radically. The German Command decided to transfer half its fleet to the Baltic to break through to the Gulf of Riga and destroy the Russian ships anchored there. Under the command of Vice-Admiral Eggard Schmidt, numerous mine-sweepers, fifteen German battleships, three battle cruisers eleven cruisers, and 56 destroyers approached the Irben Strait. This German armada was held in the Strait for ten days by the comparatively outdated Russian battleship Slava, under Captain Sergey Vyazemsky. Supported by the armoured gunboats Khrabry and Grozyaschy and several destroyers, the Slava repulsed all enemy attempts to break through the minefield. On the night of 4 August, Schmidt sent his newest large destroyers, V-99 and V-100, into the Gulf, where they were met by the destroyer Novik under Captain Mikhail Berens. In the short battle that followed, the Novik damaged both German ships, and V-99 was driven into the minefields, where she struck a mine and sank.
The German dreadnoughts Nassau and Pozen managed to force the Slava aside and enter the Gulf of Riga, where Admiral Schmidt lost the destroyer S-31. Russia's only loss was the gunboat Sivuch, commanded by Captain Pyotr Cherkasov. The Sivuch had fought in the darkness for nearly an hour in an unequal battle with the cruiser Augsburg, two destroyers and the newly-arrived Nassau and Pozen. The heroic vessel fought to the last, then sank under the ensign of St. Andrew. The year closed in the Baltic to the accompaniment of exploding Russian mines, striking the enemy cruisers Bremen, Danzig, Lubek and the destroyers V-191 and S-177.
In May of 1916, the submarine Volk, commanded by Captain Ivan Messer, destroyed three German transports, while, with the destroyers Novik, Pobeditel and Grom, Rear Admiral Alexander Kolchak sank the enemy auxiliary cruiser German in the Norrkoping Gulf. The Germans attempted to attack the Russians at the mouth of the Gulf of Riga in October, but this retaliatory action proved to be a disastrous miscalculation. Of Captain Viting's eleven newest destroyers, seven struck mines and sank.