For the longest time, historians have glossed over the relations between the Eastern and Western Axis powers as shallow and unimportant. This perception has only been reinforced by disgruntled Axis officials theirselves, some of whom denied the alliance’s importance so as to ease their prosecutions, and it is all too easy for casual observers to agree with this conclusion after spotting instances of poor teamwork, like when Berlin failed to notify Tōkyō in advance about the German–Soviet Pact in 1939.

Au contraire, historian Daniel Hedinger published a book in 2021 titled Die Achse: Berlin-Rom-Tokio, 1919–1946: an iconoclastic reassessment of the supposed ‘hollow alliance’ between the Axis powers. Unfortunately for us, Herr Hedinger’s book is unavailable in English as of this writing, but I still have reasons to offer that the relations between the Western and Eastern Axis are, if nothing else, worth reexamining.

For example, quoting Rotem Kowner’s ‘When economics, strategy, and racial ideology meet: inter-Axis connections in the wartime Indian Ocean’:

During the first years of the war in Europe, economics and the settlement of economic disputes formed the crux of Japanese–German relations. Upon the [Fascist] conquest of the Netherlands and France, and even more so after the [Imperial] takeover of Southeast Asia almost two years later, the two nations were still grappling with various forms of economic discord, especially over their respective rights to exploit the natural resources of the French and Dutch colonies in Southeast Asia.

However, as the fighting in Europe continued, economic issues (notably shortages of certain raw materials) became a growing motive for improving relations between the two nations. During their negotiations, both sides had pressing needs that could not wait for the conclusion of the imminent agreement. Tōkyō required certain military technologies and some raw materials that its main European ally already possessed, and also needed new markets for its Southeast Asian products in order to keep the local economies alive.

Berlin, in contrast, was desperate for certain raw materials that its Asian ally monopolized in Southeast Asia. These materials included, among others, tungsten, which was used for hardening metals (in items such as turbines and armour-piercing munitions) and for making wear-resistant abrasives; tin, which was used in alloys, as a solder, and for plating steel containers meant for food preservation; bauxite, for the production of aluminium used in various forms of military equipment such as tanks and industrial machinery; and, most significantly, natural rubber.¹²

Rubber had been used in all complex weapon systems since the early twentieth century, and thus became an indispensable raw material for wartime economies. Its military importance, alongside its growing scarcity in [the Third Reich] and its availability in the newly gained territories of the Japanese empire, made natural rubber the prime raw material present in the economic exchanges carried out by these Axis powers during the war, as well as providing an indirect impetus for the enhancement of their military cooperation.

Before the Second World War, Germany was a world leader in the development and production of synthetic rubber, primarily from coal and limestone, and later from natural gas too.¹³ Synthetic rubber was nonetheless the product of an emergency, produced because of the insufficient and unstable supply of natural rubber, and as a rule inferior to the latter.

However, the production of synthetic rubber did not meet [the Third Reich’s] projected and actual military demands. Critically, it was also inadequate for the production of high-performance engineering and military components.¹⁴ For instance, synthetic rubber tyres with large cross-sections tended to crack, especially at low temperatures. Hence, natural rubber remained an essential material for the production of many military articles from gas masks to large tyres.¹⁵

Natural rubber had one major disadvantage, however, as far as the European Axis countries were concerned. It could not be produced in Europe or in any other territory occupied by Germany or Italy. Extracted mostly from the tropical Pará rubber tree, it was mainly produced in Southeast Asia (85% of world production in 1939). Its largest producers were British Malaya (present-day Malaysia and Singapore), with 39% of world production, and the Dutch East Indies (present-day Indonesia), with 38%.¹⁶

[…]

A major turning point in the [Third Reich’s] quest for Southeast Asian rubber occurred on 7 December 1941, with the [Axis] onslaught on Pearl Harbor and the subsequent outbreak of the Pacific War. In the following months, [the Empire of] Japan took over both Malaya and the Dutch East Indies, the world’s leading exporters of natural rubber. [The Chancellor] could not conceal his delight at the abundant ‘rubber, oil, zinc, tungsten, and a number of other products’ which fell suddenly into [Axis] hands, remarking that ‘Japan will be one of the richest countries in the world. What a transformation!’²⁵

The joy over the presumably easy access to rubber was short-lived as the Allied powers did their utmost to prevent [Europe’s Axis empires] from obtaining natural rubber and other raw materials. Soon, a bitter struggle for the procurement of natural rubber began to take shape on both sides.²⁶

Loading their cargo directly in Southeast Asian ports, blockade-runners remained the only means for transporting rubber and other raw materials to [the Third Reich]. They usually circumnavigated Africa and carried back from Asia badly needed materials for the European Axis powers’ war effort.

Known in the Imperial Japanese Navy (Dai-Nippon Teikoku Kaigun, henceforth IJN) by their code name Yanagi-sen (‘willow ships’), between 1941 and 1944 these ships delivered 43,983 tons of natural rubber to the [European Axis empires’] war industries. They also carried 68,117 tons of other essential materials, mostly from Southeast Asia, such as tungsten, tin, and quinine, and altogether about two-thirds of the [Third Reich’s] annual requirement for these items.²⁷

These figures nonetheless conceal a dramatic development. Although by mid-1942 [the Western Axis] had unlimited access, at least in theory, to natural rubber, shipping it safely to Europe became extremely dangerous.²⁸ This situation prompted increasing cooperation between [Western Axis] commercial representatives in East Asia, but their options were limited.²⁹

While the only viable route was now via the sea, the Allies’ blockade became so effective, especially after the introduction of the Checkmate System on 8 June 1943, that fewer and fewer Axis blockade-runners succeeded in reaching Europe.³⁰ By late 1942 and early 1943, only one of the six ships that left for Europe reached its destination.³¹ As the toll of using surface ships became unbearable, this route was virtually terminated by the end of 1943.

Adding to this, the Empire of Manchuria supplied the German Reich with soybeans, the IJN inspired the Kriegsmarine’s only aircraft carrier, the Third Reich supplied the Empire of Japan with 25,000 trained dogs by December 1941, supplied it with twenty thousand Karabiner 98ks, supplied it with MP 34s, supplied the model for its E27 radar detectors, inspired the Nakajima Kikka, and more. Were it not for Allied activity, the Eastern Axis would have also acquired 20mm guns, torpedo data computers, radar blueprints, radar equipment, and a Naxos radar detector.

As we can see here, it was not a sheer lack of trying that inhibited cooperation between the Eastern and West Axis powers. There was plenty of trying, and not all of it unsuccessful: in particular, the Axis powers exhibited good teamwork when it came to conquering certain European Allied powers with colonies in Asia. When the French and Netherlandish republics fell to the Third Reich, the colonies of French Indochina and the Netherlands East Indies were ripe for the Empire of Japan’s taking.

Pictured: Fascist propaganda depicting a Regio Esercito soldier, a Wehrmacht one, and one from the IJA standing together with rifles in their hands. The text reads, ‘Three folks, one war!’

Pictured: Fascist propaganda depicting a Regio Esercito soldier, a Wehrmacht one, and one from the IJA standing on a battlefield with tattered Allied flags thereon. The text reads, ‘To conquer!’

True, the Eastern and Western Axis armies never fought side-by-side on the same battlefield (unless you count the submarines Luigi Torelli and Comandante Cappellini), but such close coordination was rare between the Eastern and Western Allied armies, too. Now, there is a rumour that Berlin had a plan for South Asia after defeating the Soviet Union: Operation Orient, wherein the Wehrmacht and the IJA would have shaken hands in India, but such a plan probably never existed.

On the other hand, Kantokuen, a plan wherein the Empire of Japan would have invaded the far eastern Soviet Union, was indeed something that Tōkyō seriously contemplated. This possibility, incidentally, explains Berlin’s infamous decision to declare war on Imperial America. Quoting Jacques R. Pauwels’s The Myth of the Good War, pages 71–72:

On December 7, 1941, Hitler, in his headquarters deep in the forests of East Prussia, had not yet fully digested the ominous news of the Soviet counteroffensive in front of Moscow, when he learned that, on the other side of the world, the [Eastern Axis] had attacked the Americans at Pearl Harbor. We will soon deal with the background and significance of this attack, which brought the U.S. into the war.

At this time it ought to be pointed out that it caused the U.S. to declare war on [the Empire of] Japan, but not on [the Third Reich], which had nothing to do with the attack and had not even been aware of the [Eastern Axis’s] plans. Hitler had no obligation whatsoever to rush to the aid of his [Imperial] friends, as is claimed by some American historians, just as the [Imperial] leaders had not felt an obligation to rush to Hitler’s side when he went to war against Poland, France, and the Soviet Union.

However, on December 11, 1941 — four days after Pearl Harbor — the [Reich’s] dictator suddenly declared war on the U.S. This seemingly irrational decision must be understood in light of the [Axis] predicament in the Soviet Union. Hitler almost certainly speculated that this entirely gratuitous gesture of solidarity would induce his Far Eastern ally to reciprocate with a declaration of war on the enemy of [Fascism], the Soviet Union, and this would have forced the Soviets into the extremely perilous predicament of a two-front war. (The bulk of the [IJA] was stationed in northern China and would therefore have been able to immediately attack the Soviet Union in the Vladivostok area.)

Hitler appears to have believed that he could exorcize the spectre of defeat in the Soviet Union, and in the war in general, by summoning a sort of [Imperial] deus ex machina to the Soviet Union’s vulnerable Siberian frontier. According to the German historian Hans W. Gatzke, the Führer was convinced that “if Germany failed to join Japan [in the war against the United States], it would […] end all hope for Japanese help against the Soviet Union.”²⁵

But [the Eastern Axis] did not take [Berlin’s] bait. Tōkyō, too, despised the Soviet state, but the Land of the Rising Sun, now at war against the U.S., could afford the luxury of a two-front war as little as the Soviets. Tōkyō preferred to put all of its money on a “southern” strategy, hoping to win the big prize of Southeast Asia — including oil-rich Indonesia and rubber-rich Indochina — rather than embark on a venture in the inhospitable reaches of Siberia. Only at the very end of the war, after the surrender of [the Western Axis], would it come to hostilities between the Soviet Union and [the Empire of] Japan.

(All emphasis added.)

Now, this was undeniably a costly mistake, and Tōkyō’s refusal to take the gamble may indicate poor teamwork, but one could also argue that it was exactly because of the Third Reich’s faith in the Empire of Japan that Berlin joined it in its war on Imperial America, hoping to encourage Tōkyō to redeclare war on the Soviets. Besides, the IJA had defeated the Imperial Russian Army in 1905, and for a while the Soviet regions of Kamchatka and Northern Sakhalin were under Imperial occupation until 1925. With all of this context in mind, Berlin’s declaration of war on the Yankees was not as reckless as it first seemed.

Further reading: Transnational Nazism: Ideology and Culture in German-Japanese Relations, 1919–1936

Transnational Encounters between Germany and Japan: Perceptions of Partnership in the Nineteenth and Twentieth Centuries

Ultranationalism in German–Japanese Relations, 1930–45

Japanese–German Business Relations: Cooperation and Rivalry in the Inter-war Period

Japanese–German Relations, 1895–1945

Japan and Germany: Two Latecomers to the World Stage, 1890–1945

‘The German and Japanese Empires: Great Power Competition and the World Wars in Trans- Imperial Perspective’

‘Shaping Japanese Fascism by European Cultural Transfer’

‘Colonial crossovers: Nazi Germany and its entanglements with other empires’

‘The fascist new–old order’

‘Germanisation of Japan and a little viceversa: A time of mutual promotion and National Socialism’

‘Creating Japan’s Propaganda: Shaping the Nation by Implementing Methods of German–Italian Fascism’

‘Japan’s Renouncement of the West: Using Methods of German–Italian Fascism’

Mutual Perceptions and Images in Japanese–German Relations, 1860–2010