Why would the Germans invade the Soviet Union? They had enough wars already, surely, and the USSR was larger than all their other conquests combined. What exactly possessed them to take the leap?
There are realms of information available on the exact dates, times, context, and consequences of Operation Barbarossa already. It is one of the largest military actions of the war, was one of the greatest turning points, and is arguably the greatest military folly the Third Reich would ever commit.
The effects of the Eastern Front are understandably enormous. More Germans died there than in every other theatre of war combined, and by a large margin. The Soviets lost an even greater number. It would influence the post-war situation in Europe through the Iron Curtain and the emergence of the USSR as a military superpower with a perhaps deserved paranoia of invasion. Not all of it was directly a consequence of Barbarossa, as later decisions in the East by both Axis and Allies and events in other theatres would play a part, but Barbarossa was the causal keystone.
The Nazi motivations for Barbarossa are less exact in literature. Within many history books on the overarching Eastern Fronts there are occasionally lists of reasons and rationales given for the Operation, but the relative significance of each is a murky and subjective area.
Used here are official Nazi documents and treaties, as well as secondary accounts of the War by later historians. I steered clear of autobiographies and the like as by the time most were written the world was very different and the aim of the authors was to rehabilitate their actions (I’m looking at you Albert Speer). I made an exception with Mein Kampf, as it was written before the war commenced and was more of a blueprint than a biography. For the documents I leaned heavily on the Anti-Comintern Pact, the Molotov-Ribbentrop Treaty, and the Führer Directives. Of the historians I had a half-dozen or so, but a special mention to Chris Bellamy’s “Absolute War” and Gerhard Weinberg’s “A World at Arms”, for their deeply grounded and well-structured accounts.
Before locating reasons, we must look into the structure of the Nazi State and how it made decisions. Barbarossa is great example of a unilateral declaration of war, so the topic is confined to German actions and does not cover the Soviet response. It turns out the Nazis had a very murky system that cared little for due process. Hitler was preeminent and had the final say on policy both foreign and domestic, but his subservient ministries were quite weird. As far as I can tell their jurisdictions constantly fluctuated and usually overlapped each other far more than contemporary systems in the USSR, Italy, or the UK. Each ministry practiced a form of social Darwinism, competing with its rivals for Hitler’s favour and support. It’s not an efficient system, but I suppose it tried to ensure the most robust ideas and individuals thrived. Thus Hitler is the central character, while also noted are the views of the OKW (German military command), Goring, Goebbels, and far down the list Ribbentrop (he really was a placeholder for Hitler’s ambitions).
Finally we come to the usual suspects when considering reasons for Barbarossa. These are nationalistic, anti-Semitic and anti-communist, economic, political and military, and accidental.
Nationalism is a key driver in boosting German views of their own strength, dismissing the strengths of both Britain and the USSR, and justifying any methods chosen to further German aims.
Anti-Semitic and anti-communist ideologies both contribute to target the USSR as an enemy of Germany above and beyond any threat they possess or any rewards peace can provide. They are constantly souring relations between the Powers.
Economically, the USSR had a plethora of natural resources and space, both of which were highly desirable to a Germany that wished to become autarchic as soon as possible. The fact of the matter was that Germany would never be able to extract more from the land directly than they traded in 1940, but in 1941 they did not yet know that.
Politically and militarily, Germany should not have attacked. Hitler saw these aspects as positives because the Russian menace would be removed, the military would gain access to Allied possessions like India, and they could link with Japan, but this wasn’t enough. Britain did not scare Germany in 1941 in the way it would later when it becomes the “unsinkable aircraft carrier”.
The only real accident would endanger the plan, not instigate war. The timetable was thrown off by the need to pacify the Balkans, but Germany pushed ahead anyway on a revised start in late June.
Of these all there was a clear winner in the end. I was surprised, as I thought political factors or possibly anti-communism would feature more heavily, but nationalism was simply everywhere. It pervaded every debate and discussion, even when not recognised as such, and it always coloured the atmosphere to a more belligerent stance instead of a more conciliatory one.