HMS Ark Royal launching Swordfish planes (painting by Robert Taylor). New weapons, brought to service during the First World War, in the course of the Second World War had eventually changed the ways of the naval warfare.

The sources of this six years long military conflict are very well known - it started from the German aggression against Poland, which triggered an avalanche of events eventually leading to the globalization of the war. It was also possible, because Western democracies too long hoped that the aggression of the Nazi state could be limited to the struggle with the Soviet Union, and too late realised the threat it posed to themselves. Wittingly or not, they helped Germany to grow to a military power on land and at sea. Different was the proper weight of the operations in individual seas, but they all were organically bound to certain strategic goals, military or political, and they all claimed the toll of human lives: those, who were maimed by elusive policies of insane fanatics, and those, who defended freedom, as they understood it.

The character of the naval operations since the beginning was predetermined by the great sea powers, which at that time were Germany, Great Britain and France in Europe, and the USA and Japan in the Pacific Ocean. During the war France ceased to count as a naval power, and simultaneously grew the role of the naval powers of Italy and the Soviet Union. The latter possessed relatively few battleships and cruisers, and so was perceived as a land power rather than a naval one. Meanwhile, the leadership of the USSR realised that the peace treaties closing the First World War (1914-1918) did not solve contradictions of the contemporary world, and extensively developed light forces of different ship classes for defence of what was expected to become a new intervention of imperialist forces against the proletarian state.

By the standards of that time five countries were considered great sea powers: United States of America, Great Britain, France, Japan and Italy. And so, they in first place were seeking domination in certain spheres of influence. Each conducted its own policy and perceived others as potential rivals. Great Britain - the greatest colonial empire - was weakened in the course of the First World War and looked with distrust at the growing power of the United States, that claimed leadership in the capitalist world, and encroached aggressively into new markets and regions with considerable natural riches. There, however, American interests clashed with the interests of Japan - the first Asian power challenging the colonial domination of white people. France was gradually reduced to a secondary power; so was Italy, but it aspired to play a bigger role under the fascist régime. Each of them had built huge navies, which were perceived as an efficient instrument of achieving political goals, and that was a sure way of going towards a new world war for a new division of the world. The crucial role was attached to the operations in seas and oceans, which separated those powers from contested areas, perceived as attractive markets or sources of vast natural resources.

However, immediately after the First World War none of the great powers would dare to step on the path of war to achieve its goals. The horrors and troubles of the exhausting war were still fresh in the memories of the peoples, who bled in that senseless slaughter. Moreover, the revolution in Russia, and the social unrest that followed, only strengthened anti-war moods and constructed an obstacle on the way to a new armed conflict. So, the great powers postponed the decisive clash till later, and for the time being tried to ease political strains through political compromises.

The first attempt occurred on the turn of 1921 and 1922 when the United States proposed to hold in Washington a conference concerning the international relations in the Far East and naval armaments. That initiative brought signature of three agreements, which seemingly eased contradictions among the participants. The first agreement, signed by the USA, Japan, Great Britain and France, concerned delimitation of their possessions in the Pacific Ocean. Second, signed also by Italy, Belgium, Holland, Portugal and China, imposed on the participants the policy of "equal opportunities" in economical relations with China. And finally, the third agreement, signed on 6 February 1922, was supposed to guarantee the two previous ones, through limitation of the displacement of the navies of Great Britain, USA, Japan, France and Italy in proportion 5 : 5 : 3 : 1.75 : 1.75. For the basis for that limitation was taken the displacement of battleships and cruisers - ships, which at that time constituted the core of the navies; also the displacement of aircraft carriers was limited according to the rules applied to the battleships, although without strict regulations, as carriers at that time were classified as auxiliary ships.

Only the United States were satisfied with the outcome of the Washington Conference, as they wrestled from England her supremacy at sea, limited Japan's influence in China, and put America in the role of the arbiter in the Anglo-Franco-Italian naval rivalry. But the Washington Treaty did not stop the naval arms race, as it granted relatively huge displacements to the participating navies. All the parties to the treaty kept developing their navies intensively, especially that many ships, built before or during the First World War had to be, partially out of necessity, by new units - more modern and powerful ones.

The Washington Treaty was supposed to be valid till 31 December 1936. But already eight years after its conclusion discontent parties tried to amend its provisions. This way came to the naval conference in London. It addressed the problem of the number of battleships in individual navies and limitations of the displacement of other classes of the ships. A partial agreement in those matters was achieved, but it was still valid till 31 December 1936. Reduction of the number of battleships did not spark many controversies, since many ships of that class had been decommissioned anyway due to their age and maintenance costs. But France and Italy refused to limit the number and displacement of their destroyers and submarines.

Once again, only the United States were satisfied with the new agreement. Great Britain was granted the right to extend its fleet of destroyers and submarines, but its power was reduced as the British forces had to be dispersed all over the world to defend vast colonial possessions. Japan did not have too much say during the conference and nursed the feeling of injustice. Japanese admirals expressed their discontent openly, and if they agreed with the new limitations, it was only because they had already realised the growing power of the air forces in the naval battles, and postulated development of this service, not limited by any treaties. The Japanese, against the views of the British or American strategists, attached a big importance to the naval aviation and saw in it the instrument of balancing the Anglo-Saxon domination at sea. The French and the Italians did not sign the new agreement, and the remaining three powers, enjoying supremacy in capital class ships, did not see in it anything dangerous to their interests. So, regardless of all the international treaties, the naval arms race flourished on.

Neither the USSR nor Germany took part in the conferences of Washington and London. In 1922 the Soviet Union, where the civil war had just ended, possessed only relics of the former Russian imperial navy, and in 1930 the Red Navy was still in development and the USSR was not perceived as a naval power at all. Moreover, in the foreign policy the USSR pursued universal and complete disarmament under the control of international political bodies, and that was unacceptable to the great powers. Completely different was the question of Germany.

German navy, which 1914-1918 was second only to the Royal Navy, by the Treaty of Versailles was reduced to a residual size. Additional agreements deprived Germany of submarines and air forces, and put the German shipbuilding industry under the strict control of the Allied powers. Also there were many provisions concerning ships' armament, displacement and service. Such a navy could not possibly pose a threat to anybody, and this was probably why Germany was not invited to the major naval conferences. Meanwhile, German authorities had been undertaking whatever effort that was possible to exploit weak points of the Versailles system to their advantage, or to conceal direct breaches in the existing agreements, to build and modernize their naval forces. And so, in 1930, the German navy, although on paper still small and weak, in fact became world's sixth sea power. The Germans, in fact, were joining the arms race among the leading five powers, and that meant nothing less but heading towards a new war - a retaliatory war. So far it was realized secretly, but the circumstances were bound to change very soon.

Within less than three years after the conclusion of the London Treaty, Great Britain and France, during the XIII General Assembly of the League of Nations, declared intention to grant Germany equal opportunities in armaments. Also the United States came out with a similar declaration. Of course, it was stipulated that German armaments pose no threat to third countries, and a system of international security had to oversee German them, but such a system had not been worked out, even less so after Adolf Hitler came to the power in Germany (1933).

Nazi Germany started dismantling the Versailles system openly. First, its navy expanded to the dimensions allowing it to operate in the whole Baltic and North Seas. Of course, Germany did not have a navy powerful enough to challenge the Royal Navy openly. Building of such a navy required time and resources, and seemed unreal, especially that it could provoke an armed British intervention. Therefore, the new German leadership had to abandon the old German imperial strategy and think about building of a fleet capable of disrupting England's sea communications with her colonies. Had the influx of food and supplies to the British Isles ceased, their economy would have been hampered to the point that Britain would have not be able to conduct the war and would have to surrender to the terms imposed by Germany.

Such a strategy required appropriate strategic position: domination in the Baltic Sea, which constituted Germany's rears, and deployment of the naval forces in the Scandinavia. It meant that Germany needed to occupy Denmark and Norway, and neutralize Poland. The latter meant an armed conflict, since Poland, confident in her alliance with France, would not yield to the German demands, and war with Poland meant also war with France. Germany stepped on the path of war as soon as in 1934, as it left the League of Nations and announced a programme of forced shipbuilding. Then there was introduced the universal conscription for the military service, and the programme of development of the air forces.

Western democracies did not oppose such a defiant demolition of the Versailles treaties. It fostered understandable worries among Germany's neighbours, threatened by the German territorial revisionism, but each country tried to solve its military problems on its own and seek political compromise with Germany. Threatened by the German aggression, not only they failed to work out a system of collective security, but even tried to feed the Nazi beast at the expense of others.

But intensive German armaments also threatened interests of great powers, in the first place Great Britain, France and the Soviet Union. They too augmented their defence efforts, and simultaneously sought diplomatic ways of avoiding a military conflict. Great Britain assumed in this mattes a very peculiar position: it did not oppose expansion of the German land and air forces, deemed less dangerous to the British Empire, but fiercely battled German efforts to expand its navy. Yet Britain assumed the policy least safe for the European peace: instead of demanding from Germany strict compliance with the clauses of the Treaty of Versailles, which she signed too, Britain decided to conclude an agreement to limit German naval armaments to the dimensions deemed safe to her own interests. To Germany it was like a gift from the heavens, so no wonder that the appropriate treaty was signed in London on 18 June 1935.

The Treaty of London allowed Germany to build a surface fleet not bigger than 35% of the displacement of the British surface fleet, and a submarine fleet not bigger than 45% of the displacement of the British submarine fleet. The proportion of the numbers might testify to a success of the British diplomacy, but in fact it was a major setback - considering the size of the Royal Navy, it opened before Germany the gate to practically unlimited naval armaments. Germany exploited it utterly and launched a programme of forced expansion of her naval forces.

When Great Britain signed the treaty with Germany, she did it to secure her own interests, without consulting other great or small naval powers; therefore England practically sanctioned German armaments, their expansion and augmentation. She also did it at the most inconvenient moment, when the validity of the treaties of Washington (1922) and London (1930) was about to expire. The Anglo-German treaty changed the parity of the naval forces, making Germany the third sea power after the United States and Great Britain, and ahead of Japan, Italy and France; the latter being directly exposed to the aggression of her German neighbour. In such circumstances maintaining the old balance of power was out of question. European security system became disbalanced, contradictions between major powers augmented, and arms race became invigorated again. The second sea armaments conference, convened in London in 1935 to extend treaties of 1922 and 1930, showed it very clearly.

The second London conference was attended by the delegations of the United States, Great Britain, Japan, France and Italy. Germany was not invited to participate, but the spectre of her naval armaments and British compromise was haunting the debates. Three months of talks ended in complete fiasco. Japan, encouraged by the compromise between the Western democracies and Nazi Germany, demanded to be treated on equal foot with the United States and Great Britain, and once her demands were rejected, the Japanese delegation left the conference. Italy refused to sign the final agreement under the pretext that she was under the sanctions of the League of Nations since the Italian invasion of Abyssinia (Ethiopia). The remaining three delegations were chiefly interested in limitation of the naval forces of their primary rivals, that is Japan and Italy; with those two countries withdrawing from the agreement the other three ones saw no purpose to impose any limitations on themselves. The conference ended in signing unimportant protocols, which after all were not observed by any party.

The second conference of London in fact put the end to the naval disarmament. World's sea powers launched a new spiral of arms race leading them surely and inevitably to a new world war. The flame of the war could burst out at any moment in any place, but with time it became more and more clear that its seat was in Germany. Political developments caused that the war broke out sooner than the participants completed their armament programmes. After Germany's aggressive actions in Europe, and failed attempts, made behind the scenes, to redirect the German aggression against the Soviet Union, Great Britain, France and ally, Poland, were forced to defend their interests the armed way. Thus started the most horrible war in the human history.