Soviet forces The Russian
Baltic Fleet was the key naval force available to the Bolsheviks and essential to the protection of
Petrograd. The fleet was severely depleted after the First World War and Russian revolution but still formed a significant force. At least one
Gangut-class battleship, as well as several
pre-dreadnought battleships, cruisers, destroyers and submarines were available. Many of the officer corps were on the White Russian side in the Civil War or had been murdered, but some competent leaders remained.
British forces A
Royal Navy squadron was sent under
Rear-Admiral Edwyn Alexander-Sinclair. This force consisted of modern
C-class cruisers and
V- and W-class destroyers. In December 1918, Sinclair sallied into Estonian and Latvian ports, sending in troops and supplies, and promising to attack the Bolsheviks "as far as my guns can reach". In January 1919, he was succeeded in command by Rear-Admiral
Walter Cowan. The deployment was unpopular among the Royal Navy sailors and there were minor
mutinies in January and again in the autumn of 1919.
Main actions The British intervention began soon after the Armistice which ended the First World War. Within a week of the war ending, an Estonian delegation had arrived in London asking for help in the shape of troops, ships and arms. The
War Cabinet quickly took the decision to send a substantial naval force to the Baltic but on no account to provide troops. British forces denied the Bolsheviks the ability to move by sea, Royal Navy ships bombarded the Bolsheviks on land in support of Estonian and Latvian troops, and provided supplies. On the night of 4 December, the cruiser struck a German-laid mine while on patrol duties north of
Liepāja, and sank with the loss of 11 of her crew. At this time, the new Estonian government was weak and desperate. The Estonian Prime Minister asked Britain to send military forces to defend his capital, and even requested that his state be declared a
British protectorate. The British would not meet these pleas. British cruisers and destroyers soon sailed up the coast close to the Estonian-Russian border and laid down a devastating barrage on the advancing Bolsheviks' supply lines. which at the time were shelling the port of
Tallinn. Both units were presented to the
Estonian Provisional Government and, as
Lennuk and
Vambola, formed the nucleus of the
Estonian Navy. Forty Bolshevik
prisoners of war were executed by the Estonian government on
Naissaar in February 1919 despite British protests. The new
Commissar of the Baltic Fleet—
Fedor Raskolnikov—was captured onboard
Spartak. He was exchanged on 27 May 1919 for 17 British officers captured by the Soviets and later appointed Commissar of the
Caspian Flotilla by
Trotsky. In the Baltic, Raskolnikov was replaced by
Nikolai Kuzmin. The British Naval Campaign in the Baltic, 1918-1919 Q19369.jpg|British sailors in Liepāja The British Naval Campaign in the Baltic, 1918-1919 Q19368.jpg|British ships in Liepāja The British Naval Campaign in the Baltic, 1918-1919 Q19378.jpg|British cruisers in Liepāja The British Naval Campaign in the Baltic, 1918-1919 Q19365.jpg|British ships on the way to Tallinn In April 1919, Latvian Prime Minister
Kārlis Ulmanis was forced to seek refuge on board the
Saratov under the protection of British ships. In the summer of 1919, the Royal Navy bottled up the Red fleet in
Kronstadt. Several sharp skirmishes were fought near
Kotlin Island. In the course of one of these clashes, on 31 May, during a Bolshevik probing action to the west, the battleship scored two hits on the destroyer
HMS Walker from a distance of , when a flotilla of British destroyers attempted to catch the outgunned Bolshevik destroyer
Azard.
Walker, which acted as a lure, suffered some damage and two of her crew were wounded, while the other British destroyers eventually disengaged when they came too close to Bolshevik
coastal artillery and
minefields. Admiral Cowan soon realised that Tallinn was not an ideal base of operations and sought a base closer to Kronstadt. On 5 June Cowan and his naval units arrived at the new anchorage at
Björkö Sound, which proved ideal for actions against Kronstadt. However, on 9 June the Soviet Navy's destroyers
Azard and
Gavriil launched a raid on the location, The action prompted the British to lay several new obstacles and minefields to protect the anchorage. Cowan also requested that Finland allocate a squadron of ships to provide additional protection for the anchorage as well as to take part in the security and patrol duties in the area. The
Finnish Navy complied and sent several gun and torpedo boats as well as motor minesweepers to Björkö. The attackers also managed to sink the important Russian submarine depot ship. The British claim that the motor boats damaged the
Petropavlosk is dismissed by Soviet records. The first raid was intended to support a significant mutiny at the
Krasnaya Gorka fort which was eventually suppressed by the guns of the Bolshevik battleships. The
second raid resulted in the deaths of 6 officers and 9 other ratings, and 9 others were taken prisoner. The White army's offensive ultimately failed to capture Petrograd and on 2 February 1920, the
Republic of Estonia and
Bolshevist Russia signed the Peace
Treaty of Tartu which recognised Estonian independence. This resulted in the withdrawal of the Royal Navy from the Baltic. Due to a request from Cowan that the Finnish squadron remain in the region until he evacuated all his forces, three Finnish
C-class torpedo boats became stuck in the ice when winter froze over the sea, and the expanding ice crushed the hulls and sank the vessels. The accompanying larger
S-class torpedo boat survived because of its stronger hull while small motor minesweepers survived as they were simply pushed out of the water by the expanding ice. The last remaining
C-class torpedo boats were placed in reserve after this incident. Significant unrest took place among British sailors in the Baltic. This included small-scale mutinies amongst the crews of , —the latter due in part to the behaviour of
Admiral Cowan—and other ships stationed in
Björkö Sound. The causes were a general
war-weariness (many of the crews had fought in World War I), poor food and accommodation, a lack of leave, and the effects of Bolshevik propaganda. ==Casualties and losses==