The military conquests of Hitler’s Germany have often been explained as a reaction to the ‘dictated’ settlement of Versailles, or as a product of Hitler’s own fantastic ambitions for world domination. They are much better understood as a classic example of geopolitical calculation, and a manifestation of the broader influence of early 20th-century geopolitical discourse in stimulating and legitimising territorial expansion. Incorporating geopolitics into the historical explanation for German imperialism also reflects a current revival of interest in geopolitics as an explanatory model, shared by both historians and historical geographers.

The key to understanding the strategies pursued during the Hitler dictatorship is the concept of ‘territoriality’ – a concern with Raum, a word usually rendered not very successfully in English as ‘space’. When the term was first used by the German geographer, Friedrich Ratzel, it was understood not to refer to a particular geographical location, but rather to denote the space necessary for a people to be supplied with adequate land and resources in order to permit a superior race and culture to survive. Ratzel was the first to call this kind of space ‘living space’ (Lebensraum). With this deeper meaning, the concept of ‘space’ had an essentially geopolitical character, because additional territory was regarded as the fundamental condition for the political health and economic viability of the race. The idea of space as a fundamental issue for German identity in the late 19th and early 20th centuries derived in part from a continual concern with the nature of the geographical character of Germany as a very recently created nation. The Reich, founded in 1871, was an artificial construction and as such prompted uncertainty not only over the internal unity of the federal system, but also over the ‘unfinished’ character of the German nation, which had failed to incorporate all Germans (the ‘Gross- deutsch‘ solution) or to acknowledge the wide cultural and linguistic influence that Germans had historically exercised in central and eastern Europe. Concern with adequate space also reflected the insecurity felt by German politicians and intellectuals that Germany had arrived too late to share properly in the spoils of European overseas empire. Although Germany was allowed limited colonial claims in Africa and the Pacific, the imperial project was limited in comparison with the British Empire, the model for German imperialists of the relationship between geography and politics, space and power, and in the 1920s and 1930s a model for Hitler and the National Socialist leadership.

The need for Lebensraum, both as a geographical resource and an expression of the political and cultural superiority of a young and dynamic nation, long pre-dated the Hitler dictatorship and became the stock-in-trade of a great many German nationalist thinkers, including a generation of German geographers. The extent to which Hitler was indebted to these discourses has been much contested, but the evidence seems incontrovertible that the concepts and language developed to support the new discipline of geopolitics was understood by Hitler and expressed clearly both in Mein Kampf, written in 1924–25, and in the so-called ‘Second Book’, written in 1928 but never published. In that first book, Hitler wrote: ‘Only an adequate large space on this earth assures a nation freedom of existence.’ There was even an indirect link for Hitler to the British geographer, Halford Mackinder, generally regarded as one of the founding fathers of geopolitical thinking. In 1904, Mackinder wrote an essay in the Geographical Journal on the ‘Geographical Pivot of History’ in which he developed the idea that control of the geographical space of Eurasia would allow a power, or powers, to dominate the rest of a closed global system by virtue of the wealth of resources it offered and the possibilities opened up by modern land transport. In 1919, he elaborated the idea of the Eurasian ‘heartland’ as the future world dominator. Mackinder’s purpose was to warn the British Empire that technological advances might be tilting world power away from the maritime empires and back to the Eurasian heartland, which for centuries had provided waves of conquering invaders of the ‘inner periphery’ in Europe, China and the Middle East.

Mackinder’s central argument found a receptive audience among those German nationalists who had long promoted the idea of a metaphorical ‘east’ to be conquered and civilised as German space. Among them was the geographer Karl Haushofer, who read the Pivot essay and the idea of the heartland shortly after the end of the First World War and cited them in a paper produced in 1921. Haushofer was impressed by the connection made by Mackinder between a geographical reality and the political consequences that might flow from it. The idea of a massive continental bloc independent of Anglo-Saxon economic and naval power appealed to him, and he continued to develop the idea of a German role in creating the ‘inner line’ of the heartland, perhaps in alliance with Russia and Japan. He founded the journal, Zeitschrift für Geopolitik, in 1924, and played a central part in creating geopolitics as a form of what he called ‘applied political geography’. Hitler came into contact with the Munich-based Haushofer through his National Socialist colleague and future deputy, Rudolf Hess. Hess was an enthusiast for the new science of geopolitics and seems to have been the conduit through which Hitler became familiar with the ideas not only of Mackinder and Haushofer, but with other political geographers, and in particular Ratzel’s Political Geography and the idea of living space. Haushofer later claimed that Hitler displayed ‘geopolitical mastery’, and it is clear that Hitler’s reflections on the nature of global political geography, and the importance of establishing adequate space for the race to develop and display its quality, are prominent features of his writing. It is not unlikely that Hitler took from Haushofer the idea that ‘space-conquering peoples’ were destined to overturn the older ‘space-resisting’ empires and forge a new continental order.

There was, nevertheless, no obvious straight line between Haushofer’s thinking and Hitler’s, nor evidence that Hitler really understood the implications of the heartland theory. The material from Hitler’s own book collection shows an eclectic interest in contemporary literature around the issue of space. Hitler almost certainly derived more from Ratzel, but there were a great many geographical and spatial concepts available to him in the 1920s as German intellectuals wrestled with the challenges posed by the territorial dismemberment of Versailles and the loss of Germany’s small but symbolic overseas empire. For example, the geographer Albrecht Penck argued that a nation was defined by its natural cultural and racial basis and produced a famous map of the alleged German ‘racial and cultural area’ (Volks- und Kulturboden) which showed German space expressed through cultural and ethnic footprints that stretched throughout eastern Europe and far into the Soviet Union, an argument that resurfaced regularly in the Third Reich. This argument relied much on racial categories, as did Hitler’s geopolitical outlook. His reading of modern biological theories of race and genetics coincided with his introduction to geographical ideas of space but separated him from Haushofer, whose ideas were not racially founded, except in his hostility to Anglo-Saxon hegemony. Theories of race were linked closely with contemporary ideas of empire that were European-wide. Hitler borrowed extensively from Social Darwinist biopolitical paradigms to underpin not only his view of the superiority of the German race as a ‘bearer of culture’ (Kulturträger), but also his visceral anti-Semitism. His view of the Jews as a people without a nation, cosmopolitan conspirators whose role was to emasculate true nations, also dated from the early 1920s; it is tempting to see this interpretation as geographical as well as racial, for in Hitler’s view the Jews were without space, an anti-nation, inhabiting as parasites the space of others. On these terms, Hitler represented a lethal combination of political geography and racial prejudice (Rasse und Raum), that would later underpin the effort to conquer Eurasia and to exterminate the Jews.

Hitler thus came to power in 1933 with a range of intellectual influences that shaped his view of the future racial state and the expansionist policy that the new Germany was to follow. Geopolitics (‘applied political geography’) was an important element not only in his thinking but in the outlook of many of the radical nationalists who crowded into the National Socialist Party in the early 1930s. There were many other elements that conditioned the way that strategy was developed and articulated, not least the reaction of other states to a rapidly rearming Germany, but the role of German intellectuals and scientists in shaping the conceptual world that Hitler inhabited has too often been underestimated in favour of the contingent world of diplomacy. The key metaphor of space to the east, which had dominated much German spatial thinking since the 1890s, emerged as a central element. For German imperialists, it was important that the space should essentially be empty of order and racial value, much as Europeans had viewed the ’empty’ spaces of North America, or Africa or Australia as areas fit for colonisation. The ‘east’ was appropriated by geographers, anthropologists and ethnographers as a space that required German order, as well as a space that would help fulfil Germany’s territorial and cultural destiny. In 1941, the writer Bruno Brehm described to the German Writers’ Congress his view of the East: ‘There we may shape what is yet without shape, form what is yet without form. We may ban chaos from there and we may advance our own dominion.’

Though Hitler never cited Mackinder directly, his thinking mirrored the geographer’s view that control of central and eastern Europe was the key to control of the Eurasian heartland. Hitler was well aware of the rich resources that lay in the Soviet Union, control of which would turn Germany into a superpower. In a speech in 1936 at the annual party rally, he asked his audience to imagine a German-dominated Eurasia: ‘If the Urals with their immeasurable raw material riches, Siberia with its rich forests and the Ukraine with its measureless areas of grain lay in Germany, under national-socialist leadership, the region would swim in surplus…every single German would have more than enough to live on.’ He also thought in large historical terms about the threat posed by the Soviet Union. In the only major memorandum that Hitler wrote during the dictatorship, the ‘strategic memorandum’ of August 1936 (usually known as the Four-Year Plan memorandum, though that was not its title), Hitler reflected on the long millennia in which Asia had menaced European civilisation and the historic mission of the Germans to roll back this tide by preparing for large-scale war over Eurasia. It was a vision that Mackinder would have approved of, since his own thoughts about the heartland had also relied on a historical perspective going back centuries. However, when the time came to prepare for war against the Soviet Union in 1940–41, circumstances had changed entirely. War with France and Britain in September 1939 was not what Hitler wanted because it undermined the thrust of his geopolitical transformation of eastern Europe, though it did not halt it. The plan to invade and destroy Soviet power now derived from the circumstances of the summer of 1940, after the victory over France but with the British Empire still undefeated. Failure to create conditions for invasion of Britain in the autumn of 1940 pushed Hitler to the conclusion that defeat of the Soviet Union was a necessary step to force British capitulation, first by removing any prospect of a major European ally, and secondly by gaining the material resources to underpin a military contest with the West.

But once the decision was made, the geopolitical ambition to control the Eurasian heartland, supported by the assiduous activity of geographers, anthropologists and ethnographers now working for institutes set up by Heinrich Himmler’s SS, became paramount. Hitler hoped that the resources embedded in Eurasia would supply what was necessary to defeat the Anglo-Saxon powers and confirm the prediction made in 1919 by Mackinder that whoever controls the heartland (the ‘world island’) would dominate the globe. Mackinder had argued that technology, above all the railway, had transformed the strategic possibilities for whichever powers occupied the heartland. Hitler brought that argument up to date with plans for high-speed Autobahnen (highways) that would reach out across the Eurasian space, transforming the possibility of its development, but also ensuring that power could be projected wherever it was needed to safeguard the heartland’s security. The paradigm used by German planners was essentially a colonial one. Though historians debate whether there was any direct continuity between German pre-1914 imperialism and the new project in Eurasia, there is no doubt that those engaged in the conquest and pacification of the new geographical zone thought in terms borrowed from the prevailing practice of territorial empire and the long history of racial discrimination and extermination that had accompanied it. Hitler’s famous comment that ‘Russia will be our India’, though it revealed how little he understood British imperialism, also revealed the extent to which the German project was seen as an extension of an existing geopolitical reality. The harsh racial policies, including the eradication of the Jewish population in the East, were part and parcel of a larger ethnic project which foresaw the Germanisation of Eurasia and the extermination of up to 30 million so-called ‘useless eaters’. The remodelling of the entire area was at the core of General Plan East, an ambitious project for the geopolitical transformation of the Eurasian heartland.

The problem confronting Hitler (and the party’s planners and geographers) was obvious at the time. The Soviet Union was not ’empty space’, but was a rapidly arming and modernising industrial giant, with a well-organised state apparatus and a strong sense of identity as the world’s first communist state. Though the invading Germans sneered at what they viewed as primitive living conditions and ‘bestial’ people, when the war ended in August 1945 the whole of Mackinder’s heartland was occupied by the Red Army, from central Europe to Manchuria, and a new era of geopolitical thinking opened up as the Western states confronted the vast Communist bloc constructed after the war’s end. The imperial fantasy that had fed German nationalism for decades was overturned and the metaphorical ‘east’ became a real east of powerful and vengeful armies bent on destroying Germany’s imperial endeavour entirely.

It is tempting to ask whether geopolitics really caused this disaster. It is clear that geopolitical categories and concepts were useful in supplying a scientific underpinning to legitimise military aggression and crude colonial practice, just as current biological theory underpinned the brutal eugenic and racist policies of the regime. It can also be argued that Hitler’s exposure to the geopolitical and imperial literature of the 1920s provided him with a language to define his intentions and to justify them in terms that derived directly from ideas about ‘space-conquering peoples’ as an expression of racial vitality and cultural superiority. It is also difficult to explain why so many among the German academic and military elite were prepared to follow his strategic course unless they shared in one form or other the central view of Germany as a nation without adequate space, denied its cultural birthright by the old imperial powers whose global order was in apparently terminal decline. Hitler, from this standpoint, reflected the worldview of a much broader constituency of Germans in the 1920s and 1930s who believed that geographical and political realities had to be altered if Germany was to achieve the destiny its people deserved. The argument that the Germans were waging a geopolitical war was popular in the wartime United States, where the work of both Mackinder and Haushofer was well known to geographers. Roosevelt’s conception of future war, in 1940–41, was based on calculations of geographical resources and the problems faced by maritime powers facing an enemy dominant on land. Recent research on the continuities in German thinking about empire and space has reinforced this earlier appreciation. It is difficult now to deny that geopolitics helped to shape the territorial and racial ambitions of the Third Reich, and that it helped to cause the war.

It is nonetheless important to recognise that German concern with ‘territoriality’ and race was by no means unique to Germany. The idea of empire as an expression of a vital and cultured people was commonplace, and was borrowed by Italy and later Japan to legitimate their own programmes of territorial expansion in the 1930s. Geopolitics was also borrowed by Italian and Japanese scholars. The journal, Geopolitica, was founded in Italy in 1939 with Mussolini’s support and a similar journal was established three years later in Japan, by which time the three Axis states had signed the Tri-Partite Pact in September 1940, stating in bald terms their common aim to recast the political geography of the globe. German thinking reflected a prevailing reality in much the same way that geopolitical argument reflected contemporary realities rather than imagining a new global order. German territorial expansion was not a case of imposing unacceptable violence on a stable world order, but a response to a world order in rapid transition which German leaders hoped to stabilise in Germany’s interest. The effort to act ‘geopolitically’, however, destroyed the new German empire because Hitler and his entourage failed to recognise the gap between geopolitical fantasies and political-military reality. Within a few years after 1945, the empires that Germany had hoped to emulate or supplant were themselves the victims of a global re-ordering in which traditional colonial empires had no place. It could be argued that the current revival of interest in geopolitics among academics and practitioners also reflects the arrival of another age of insecure and unpredictable transformation in the world order.

This essay by Richard Overy was originally published with the title Geopolitics and Empire in the Third Reich in The Return of Geopolitics: Perspectives from the Engelsberg Seminar 2016, Axess Publishing, 2019.