Russian Navy

Target Is to Destroy the Baltic Fleet


On the eve of the War with Finland (1939-1940), which began 65 years ago on November 30 of last year, the military and political leadership of the USSR had sufficient information on the long-standing secret Finnish-Estonian plans for conducting war against their “Bolshevik neighbor.” Naturally, Moscow could not ignore this factor in the context of the Second World War that had already begun in Europe and the opportunities that presented themselves to postpone the threat of Germany and its satellite nations attacking its territory.

For years, the topic of military cooperation between Finland and Estonia throughout 1930-1939 was cloaked in a thick veil of strict secrecy. Only a few veterans addressed it - former officers of the General Staffs of the two countries of the period who lived to our day. While the search for sources of information in the Finnish archives presented investigators with great difficulties due to the fact that in September of 1944, after Finland had withdrawn from the Second World War, almost all of its General Staff documents were either burned or taken abroad. Success came unexpectedly - a Finnish historian, Jari Leskinen, discovered in the declassified funds of the Estonian National Archive new documents that shed light on the secret liaisons between military departments of the two Baltic nations during the interwar period, directed at resisting the “Kremlin’s expansion westward.”


For Finland in the 20-30s of the 20th century, Soviet Union appeared to be the only probable enemy. But in its preparations for possible war, Helsinki proceeded from the need to find reliable ally countries among both the neighboring countries and the great Western powers, including Germany that was being reborn after the Versailles. In the opinion of the Finnish strategists, that was the only way to defeat the “communist titan.”

Finland had old connections to the Third Reich from the time of the end of the First World War, when its newly born government armies were being generously supplied with German weapons. After the conclusion of the Brest-Lithuanian peace treaty, about 12.5 thousand of German troops were immediately dispatched to Finland. In turn, 2 thousand Finnish “jagers”, soon at the core of the new national army, went through military training in Germany.

While officially upholding the line of neutrality, Helsinki, under the pressure of the pro-fascist oriented political circles, continued to strengthen its secret connections with Berlin. In exchange for supply of copper and nickel, Finns received 20-mm anti-aircraft guns and shells from the Germans, arranged procurement of military aircraft, exchanged visits by high-ranking generals and officers, and in August of 1937 even hosted a squadron consisting of 11 German submarines… Such moves allowed Germany to nurture potential plans for using Finland in its aggressive schemes. On the other hand, for the Finns themselves, who haven’t forgotten their territorial claims to East Karelia from the USSR (after the Tartu Treaty of 1920), closer relations with the Germans meant solid reason to feel more confident in their search for new secret military partners in the Baltic, capable to support them in their opposition to the Soviet Union.

The year 1925 became the turning point in Finland’s military politics, once the officers, “jägers” who were trained in the Imperial Germany, replaced those who once served in the Russian Imperial Army. Characteristic of the period when the latter served in the General Staff was that all the operations planning was based on defensive war. Younger “jagers” immediately gave up this kind of approach. The principal focus of the armed forces under their new operations planning, developed under the direction of the Chief of General Staff, Colonel Kurt Martti Wallenius, became the development of offensive strategy and tactics. In connection with that, in the 20’s and 30’s, the Finnish General Staff established close connections with the General Staff of the neighboring Sweden. Military leadership of the latter, who, before Hitler came to power in Germany, considered the Soviets to be the most probable enemy, was highly interested in organizing defense of its country from possible aggression by the Soviet Union with the help of Finland and Estonia already at their eastern borders. This suited the Finns, since then, on the basis of the reached mutual agreement, the Swedes could direct their large forces to aid them. In the course of the Finnish-Swedish negotiations, for the first time an idea was born to offer Estonia, on behalf of Finland, to organize a system of mutual blockage using the armed forces and other military means of the two Gulf of Finland countries, while under no circumstances disclosing to them whose initiative it was. In case of blocking of the Gulf, Sweden could freely transport its troops through the Gulf of Bothnia to Finland and, on top of that, ensure security of the Aland Islands, vital to both of the Scandinavian countries.

The idea for development of mutually beneficial military contacts between Finland and Estonia found supporters among the political leaders of the two countries. Already in the beginning of the 30’s, they sanctioned joint military planning. For example, plan provisions that had to do with joint action with the Estonian army to block the Gulf of Finland to the detriment of the Soviet Fleet were very appealing to the Finnish President Svinhufvud. On the other hand, this offer by the Finns seemed to the Estonians to be somewhat unexpected, even though they approved. Thus, the Prime Minister and the head of Estonia, Päts, noted in 1933 that in all the previous years, Finland regarded all their military cooperation suggestions negatively, whereas now, on the contrary, it was nudging his country in the direction of tighter cooperation in the sphere of possible blockade of the Gulf.

The Finnish General Staff based its further operations planning on the assumption that the USSR would never be able to resign itself to losing Finland or the Baltic countries that were once part of the Russian Empire. Its plans even provided for possibility of attacking Leningrad and the principal naval base of the Baltic Fleet, Kronstadt. Thus, the operations plan of 1930 included the following argument to support such an attack:

“…Both the military and political, and the strategic situation require joint action with the neighboring countries. Any change for the worse in the current situation would result in deterioration of Finland’s strategic position… We must attempt to conduct military operations in such a way as to soften the situation to the South of the Gulf of Finland. Finland's task is to aid Estonia and Latvia by paralyzing the possibly larger Russian forces… To do that, it's necessary to concentrate all the resources that could be made available at the crucial moment and attempt to break through to Leningrad, which could lead to capture of the city and destruction of the Baltic Fleet… .”

It is important to note that the provisions for providing indirect help to Estonia, which for the Finns held strategic importance, were included in all the plans of their General Staff from 1930 to 1933. In the opinion of the generalship of Finland, any occupation by the Red Army of the Estonian territory would greatly damage the position of their country. In such a scenario, the USSR, placing its naval and air force bases there, would hold the Finnish naval communications and the industrial and residential centers in its reach. The Russian Baltic Fleet would be able to break through into the Baltic Sea and seize the Aland Islands, in which case the Finnish armed forces would have to fight the Soviets on two fronts.

In 1931, the ideas of the country’s General Staff were supplemented and developed further by the Chairman of the Defense Council of Finland, the well-known General Carl Gustaf Mannerheim. He developed two memorandums where he straightforwardly noted that in case of a simultaneous attack by the USSR on Finland, Estonia, and Latvia, a simple joining of their armed forces would not be enough. In such a case, external aid from across the borders, through the League of Nations, would be needed, and first of all that of Sweden. The possibility to get help from the navy and the air force from a number of western countries, in particular, from France, was also not being ruled out.

In accordance with the estimations by its General Staff, Mannerheim saw that any offensive action in the direction of Leningrad would demand great effort from the allied armies. Nevertheless, this could be possible, especially in the winter period. Best results could be reached, at the same time relieving the military situation of Estonia and Latvia, by organizing an offensive from both the Finnish territory and from the northern frontiers of Poland. As a result of such joint actions, which would not transcend the limits established by the sanctions approved by the League of Nations, in Mannerheim’s conclusion the Baltic Fleet would be forced to retreat into the upper Gulf of Finland, which would result in creation of the necessary conditions for the ultimate defeat of the Soviet armed forces.

The Finnish General Staff officers’ estimations regarding helping Estonia and Latvia were built on the supposition that if USSR engaged in a simultaneous fight with several front line states, its Red Army would not be able to attack Finland right away. It would be forced to keep its large forces at the Finnish border to protect Leningrad. This supposition was based on the information about the fortification system of the Russians on the Karelian Isthmus that resulted in presuppositions that they would use defensive tactics.

Nevertheless, the Finnish military ministry’s interest in Estonia and its military position did not die. In the second half of the 30’s, a group of senior officers with an active interest in how fast the Estonian armed forces would be able to put up resistance to the Red Army in case of war, were sent to Estonia.

And only three years later, based on the new intelligence received by the Finnish General Staff about the mobilization capabilities of the Red Army and the fleet, it was decided to give up the idea of “attacking Leningrad and providing military aid to Estonia and Latvia.” National defense plans took effect. Soon, with the General Johann Laidoner assuming command of the Estonian armed forces, adjusting the thinking regarding defense by the military staff and politicians of not only his country, but also affecting the development of the Finns’ views on strategy, the secret Finnish-Estonian military cooperation directed against the Soviet Union had received an additional impulse to be actually realized.

In particular, Laidoner requested that all the military maneuvers and exercises of the Estonian army be based on the principle of decisive resistance to the Russians already at the borders with the USSR. Building on his point that the Red Army’s armored troops are not as strong as was previously believed, the General contended that the Estonians could match them with their powerful frontier fortifications and excellent knowledge of their own territory, to be able hold out until the end. Incidentally, in September of 1939, when the USSR demanded that Estonia provides it with naval and air force bases, it was Laidoner who had enough resolve to declare nation-wide mobilization in the country. By that time, the Estonian military leadership already had too strong of a belief in its own abilities to resist the Red Army. Besides, the General, in all seriousness, counted on receiving Finnish help for the second stage of hostilities.


Analysis of the top-secret military cooperation between Finland and Estonia shows that it developed over the time period of over nine years. It started with negotiations that took place between the military ministries of the two countries already in the beginning of 1930 at the initiative of the General Staff of Finland. They took place immediately after Latvia had turned down Finland’s senior military leader, Aarne Sihvo’s idea for the development of joint plans for coordinated submarine action directed against the Soviet Navy forces at the narrow entrance to the Gulf of Finland, in 1928. That’s when Finns fixed their eyes on the neighboring Estonia, which was also separated from and united with their country by the very same Gulf of Finland.

During the very first negotiations, the Estonian Fleet commander, Rear Admiral Hermann Salza, suggested that the Soviet Union would commence the military action by installing mines in the straits between Porkkala and Tallinn to hamper marine transportation in the Gulf of Finland. To prevent that, Salza suggested that Finns place a coastal heavy artillery battery in Porkkala. In his opinion, such a battery, together with a similar coastal battery placed near Tallinn, would prevent the Soviet fleet’s breakthrough from the Gulf into the Baltic Sea. Furthermore, Salza suggested that the naval forces of the two countries put out a large mine field in the said region to increase the effectiveness of the barrier created by the coastal artillery.

The discussed suggestions about cooperation had a substantial influence on the plans for development of the naval defense of Finland. Typically, before, the Finns had never seriously considered the possibility of cooperation with the Estonians in blocking the narrow-most part of the Gulf for the Soviet Baltic Fleet. Now, after having held negotiations with the Estonians, other plans were also developed right away. They contained suggestions on fortifying Makiluoto Island (Mac Elliot Island) located near the Porkkala Peninsula, across from the coastal fortifications of Tallinn (the width of the Gulf here amounted to no more than 36 km), with a heavy artillery battery that would allow encompassing the entire Gulf of Finland in the field of fire (the effective range of fire exceeding 40 km). These same plans additionally provided for deployment of minefields in the narrow-most part of the Gulf. Thus, the Finns and the Estonians could create a defense system similar to the one that the Russian Empire had in the Baltic for protection of Saint Petersburg already in the beginning of the 20th century.

After the necessary agreements were reached, Estonia presented Finland with sketch maps and other construction documentation. Finnish and Estonian officers were instructed on getting to know each other to facilitate the tight and effective cooperation of their artillery.

At the same time, the Finnish military ministry took a number of measures to involve Estonia in the opposition to the USSR on a foreign-policy level. After having conducted secret mutual consultations between the Finnish and the Polish General Staffs in Warsaw in May of 1931, a common line of conduct was developed for all the parties for the World Disarmament Conference that was supposed to take place in the beginning of 1932. The Latvians and the Estonians were invited to join. Their main opponents at the Conference were the representatives of the Soviet Union. The Finnish-Estonian cooperation during the period of preparation and during the actual Conference was fruitful.

In the mid-30’s, by the completion of Makiluoto Island fortifications, the Finnish and Estonian military personnel started the practical stage – working on the joint blocking of the Gulf by fire. Starting at that time, the secret military exercises of the coastal artillery batteries of the armed forces of the two countries were conducted on a regular basis (the last of them took place in 1939). For example, in 1937 they were headed by the Estonian coastal defense commander, Lieutenant Colonel Carl Frimann, and his Staff. During the exercises, main attention was devoted to the practice of unified control of fire of the Makiluoto defense by the Estonians from the Finnish side. Additionally, creation of artillery barrier and coordination of allied communication systems drills took place.

Notable results were achieved in the latter. Already in the beginning of the 30’s, cooperation of the naval reconnaissance of the allies had begun, having as its goal constant surveillance of the activity of the Soviet Navy ships and vessels in the Gulf of Finland. Already in the second half of the decade, agreements were reached between the parties for joint control of the coastal artillery fire. As a result of all the drills and practice, the gunmen from the Estonian shore were able to direct the actions of the Finnish coastal artillery and vice versa. In this respect, the most important piece of the two-way communication system was the protected communications cable, connecting the Finnish and Estonian batteries and buried deep in the floor of the Gulf. Military strategists of both nations believed that joint operations of their armed forces could be realized even in the case if only one of the sides was at war with the Soviet Union, while the other maintained official neutrality. At the same time, the plan was that the coastal defense of the ally-nation at war would secretly receive full intelligence information about the Soviet Fleet from the opposite side, while the USSR would not be able to provide sufficient proof to accuse either of the nations of neutrality breach.

The Finnish-Estonian military and political connections could not remain unnoticed by the superpowers, in particular, by France, Great Britain, and Germany. The British envoy to Helsinki, Rowling Sperling, and the military attaché Sillery Weil, reported to London that:

“…The Finnish government is restructuring the coastal artillery system in such a way that, in cooperation with the Estonian batteries near Tallinn, it becomes possible to block the opponent’s navigation through the Gulf of Finland...

It seems like this affirms the wide-spread belief that a mutual understanding exists between the military authorities of the two countries, even if there is no formal alliance. It’s necessary to note that for them, the Soviet Russia is the only probable enemy…

…A strong (Soviet – by auth.) Navy in the Baltic Sea is useless unless it can count on a base that does not freeze in the winter, from which the forces could be safely deployed. Leningrad freezes in the winter, and in the summer, the opponent’s fleet, based in the Aland Islands or in the Ezel Island, or even the powerful coastal defense artillery and the strong air forces of Estonia and Finland, could foil all the operations.”

Same as between the Finland's and Estonia’s fleets, in the beginning of the 30’s, a direct two-way and telegraph communication was established between their General Staffs. The communication also used the underwater cable, allowing the two sides to exchange secret information about the Soviet Union and the nations’ defense plans without any intermediaries. Additionally, an exchange of views on the operations planning and the defense politics with respect to the USSR also took place in the course of the official and unofficial visits by the Chiefs of General Staffs. Joint military surveillance activity by the Finns and the Estonians was very extensive.

For the case of a possible war with the eastern neighbor, Finland and Estonia actively prepared their naval forces and facilities for joint actions. For example, in 1933, Estonia had to sell two of its destroyers abroad so that it could use the proceeds to build submarines in the future. In four years from then, Estonia acquired two submarines, built with consideration of the Finland's wishes.

After having mastered the two new ships, in the beginning of the summer of 1939, the allied nations’ navies conducted two secret military exercises of offensive nature that involved rebuffing of a hypothetical offensive by the Soviet Baltic Fleet from the east. According to the naval commanders’ plans, 5 submarines of the Finnish fleet and 2 of the Estonian, in case of an attack by the USSR, had to act under the unified command by the Finnish side. It was decided to carry out further drills for this military task during new exercises the following year. However, due to the commencement of the Second World War in Europe and the Soviet-Finnish War (1939-1940), as well as the annexation of Estonia to the Soviet Union in the summer of 1940, these plans did not have a chance to be realized.

Along with practical exercises by the troops, Finnish and Estonian military leaders also conducted secret tactical war games. The first of such games took place in Tallinn at the end of 1933, under the command of the Finnish Navy commander Väinö Valve. In the course of the exercise, the possibility of joint blockade of the narrow-most point of the Gulf of Finland to prevent the Soviet ships from passing, using surface ships, submarines, heavy coastal artillery batteries, and aviation of the armed forces of the both countries, was investigated. These war games resulted in conclusion of a secret agreement for a mutual exchange of coastal defense information.

It should be underlined that the official foreign policy of the Scandinavian and the Baltic states, especially in the second half of the 30's, tried to conceal in every possible way the existence of any kind of secret arrangements for joint military actions in case of war.

A mutual concern for both Finland and Estonia was the fact that their long-standing ally, Great Britain, gradually lost interest for the Baltic Region. In the summer of 1935, the English signed an agreement with the Germans, which meant that Britain gave Germany free reign with respect to strengthening its positions in the Baltic. Now the German Navy could easily interfere with any foreign fleets entering the Baltic Sea by blocking the Danish straits. This policy of appeasing the potential aggressor would very shortly become a costly mistake for the English.

And whereas before, in case of the Soviets' attack on the small nations of the Baltic Region, the Finns and the Estonians could realistically count on the English naval squadrons turning up in the Baltic, now they based all their hopes on their own secret alliance, while keeping watch on Germany that was gaining strength.

That’s why every year between the years 1933 and 1939, in complete secrecy and with the permission of the General Staff of Finland, the ships of the Estonian fleet conducted navigation drills to the Finnish shores and islands as well. In the course of these, the straits and narrow spots between the islands and the coastline were navigated under conditions close to combat conditions: beacon lights were extinguished, other aids to navigation were removed or set at improper points (naturally, the necessary field reconnaissance by the Estonian man-of-war’s men was conducted with the permission of the Finnish General Staff). The Estonians justifiably counted on their ships and vessels being able to sail to the Finnish and Swedish shores unhampered under the cover of the possible Gulf blockade.

By the end of the summer of 1939, the plan of the joint blockade of the Gulf of Finland by the armed forces of Finland and Estonia had been almost completely evaluated in theory thanks to the tactical war games and perfected in practice during field exercises.


According to the Russian archive documents, the Soviet higher military command was aware of the Finnish and the Estonian plans regarding the blockade of the Gulf, which, naturally, caused it well justified concern. And, if before Hitler came to power in Germany, the number of probable enemies in this theater of military operations included England, France, Poland, Finland, Estonia, and Latvia, unified in a possible alliance, after the 1933, among others, the Germans took place of the English and the French on top of that list. Assessing the capabilities of the German, the Finnish, and the Estonian navies as serious, the USSR was greatly disturbed by the fact that in case of war, these allies could easily thoroughly block the decorated with the Order of the Red Banner Baltic Fleet in the bottleneck of the Gulf of Finland, prevent it from acting against the German ships in the Baltic, and foil the deployment of its troops and weapons into Scandinavia and the Baltic states. Thus, when in the fall of 1939 Joseph Stalin requested territorial concessions from Finland and Estonia, he had a very clear idea why he was doing it.

Source:, authors: Igor Amosov – retired Captain of the 1st Rank, Andrei Nikolayevich Pochtarev, Candidate of Science in History

Copyright © 1998-2012 All materials contained in this Website are protected by copyright laws and may not be reproduced, republished, distributed, transmitted, displayed, broadcast or otherwise exploited in any manner without the express prior written permission from the editorial staff. The editorial staff. Site created by ProLabs. Russian version.