On the 18th December 1940 Hitler issued formal orders to the German armed forces to begin the detailed planning for the invasion of Russia, known as Operation Barbarossa.
Directive No. 21 – Case Barbarossa
The German Armed Forces must be prepared, even before the conclusion of the war against England, to crush Soviet Russia in a rapid campaign.
The Army will have to employ all available formations to this end, with the reservation that occupied territories must be insured against surprise attacks.
The Airforce will have to make available for this eastern campaign supporting forces of such strength that the Army will be able to bring land operations to a speedy conclusion and that eastern Germany will be as little damaged as possible by enemy air attack. This build up of a focal point in the east will be limited only by the need to protect from air attack the whole combat and arsenal area which we control, and to ensure that attacks on England, and especially upon her imports, are not allowed to lapse.
The main efforts of the Navy will continue to be directed against England even during the eastern campaign.
In certain circumstances I shall issue orders for the deployment against Soviet Russia eight weeks before the operation is timed to begin.
Preparations which require more time than this will be put in hand now, in so far as this has not already been done, and will be concluded by 15th May, 1941.
It is of decisive importance that our intention to attack should not be known.
On the same day Hitler gave a speech to officer cadets which outlined his philosophy, central to which was his belief that the Germany people needed more ‘living space’ or ‘Lebensraum':
There are approximately 85 million Germans in Germany. I do not even include in this figure our Low German Volksgenossen. England, the British Empire, has barely 46 million Englishmen at home. The French Empire has barely 37 million Frenchmen at home. Even the American Union, minus Negroes and Jews and Latinos and Germans, has barely 60 million true Anglo- Saxons. Russia has barely 60 million Great Russians.
And even today the unified racial core in Germany remains the largest by far; not only in value, in itself highly significant, but also in numbers, it is the greatest. By contrast, if we compare the percentage of Lebensraum occupied by the German Volk to that of the earth as such, then we must remark that our Volk is one of the most disadvantaged peoples of the world. Barely 600,000 square kilometers, in fact about 140 persons per square kilometer. 46 million Englishmen rule, control, and organize about 40 million square kilometers. Barely 60 million Great Russians rule an area of about 19 million square kilometers. About 60 million Anglo-Saxons within the American Union determine life within an area which encompasses about nine and a half million square kilometers. 37 million Frenchmen rule over life in an area of nearly ten million square kilometers.
In other words: the German Volk, in terms of the space it occupies, is by far the most modest there is on this earth.
Speech at the annual rally of young officer cadets at the Berlin Sportpalast, December 18, 1940
Whatever the military arguments around the invasion of Russia it was the perceived need to seize more ‘Lebensraum’, combined with his long standing, deep seated hatred of ‘Bolshevism’ that lay as the prime motivator behind the decision to launch Barbarossa.