Nazi dictator Adolf Hitler and his generals had been preparing for this moment for months. On Sunday, 22 June 1941, the time had come. At 3:15 a.m. the German army — the Wehrmacht — launched its attack on the Soviet Union. There was no declaration of war, and the Nazi-Soviet Non-Aggression Pact of 1939 was simply ignored.

More than three and a half million German and allied soldiers were supported by artillery, Luftwaffe aircraft and tanks as they joined forces in an advance that was rapid, ruthless and overwhelmingly effective. The Luftwaffe bombarded Soviet aircraft while they were still on the ground. The battle line extended over 1,600 kilometers (990 miles), from the Baltic Sea in the north to the Black Sea in the south, making it the longest front line in the history of warfare.

The soldiers of the Red Army were caught unprepared by the onslaught: "Some of them even came out in their nightshirts and opened fire, they were taken completely by surprise," recalls former Wehrmacht soldier Gerhard Goertz in a video that is part of the online portal at the Haus der Geschichte (Museum of Contemporary History) in Bonn.

There had been earlier warnings of what was to follow, but they were dismissed by Soviet leader Joseph Stalin. He was convinced that Hitler would not dare to attack a vast realm like the Soviet Union. As a result, there was no mobilization against the Nazi threat.

German propaganda described the attack as a preventive strike launched in response to an imminent military assault by the Bolsheviks. In reality, Hitler had ordered a ruthless campaign designed to destroy his enemy. The dictator dreamt of conquering new Lebensraum ('living space') for Germans in the east: A Greater German Reich that would reach from the Atlantic to the Urals.

Hitler's crusade

For Hitler, the war was a battle for survival between different Weltanschauungen ('worldviews') and races, a campaign to subjugate the Soviet Union. It was also seen as a crusade against Weltjudentum ('world Jewry') and Bolshevism. Tellingly, the vicious offensive took place under the codename Operation Barbarossa, a reference to Frederick I, Holy Roman Emperor (1122 – 1190), also known as Frederick Barbarossa (red beard), who had led the Holy Roman Empire in a crusade.

The massive assault was less a military campaign and more a mass crime in glaring contravention of the provisions of international law. Many of the soldiers who fought for the Nazis had been taken in by the Blut-und-Boden ('blood and soil') brainwashing that encouraged them to believe that they were members of an 'Aryan master race' far superior to the Slavic peoples: "Our commanders never tired of telling us that the Russians were barbarians, or uneducated 'Untermenschen' ('inferior human beings'). So, when it came to the Russians, there were no inhibitions," says former Wehrmacht soldier Herbert Baier on the online portal in Bonn.

"Hitler's war against the Soviet Union was a war of extermination. It went far beyond any military objectives," believes historian Chris Helmecke from the Potsdam-based Center for Military History and Social Sciences of the Bundeswehr. "Instead, it was all about the ideologically-motivated and systematic annihilation of a whole state and its population." 

"In terms of its all-encompassing criminal dimension, the German-Soviet War is indeed unique in history," he told DW.

Compelled to perform forced labor

Some 5.6 million Soviet soldiers were taken as prisoners of war by the Germans and used as forced laborers. An estimated 3.3 million did not survive the ordeal. With the support of ordinary Wehrmacht soldiers, SS units killed anybody who they believed to be Jewish.

Jews were dragged out of their houses "and told to bring their own spades along in order to dig their graves," explains former soldier Willi Hein, who witnessed some of the horror first hand.

His testimony has also been added to others at Bonn's Museum of Contemporary History. "Then they were shot and killed by members of the military police units that were known as the Feldgendarmerie." In addition, there was the notorious so-called Commissar Order, which stipulated that any Soviet political commissar detected among prisoners of war was to be summarily executed on suspicion that they were enforcers of 'Jewish-Bolshevism' among Soviet troops.

The German invaders were initially confident of victory. The Wehrmacht occupied Ukraine, Belarus and the Baltic states. Hopes also ran high that the German forces would soon enter Moscow.

But they never fully managed to break the Red Army's resistance. What followed was a long and bloody war. The Wehrmacht was pitifully equipped for the desperately cold winter temperatures, which could plummet to minus 50 degrees Celsius.

No strategy for long-term conflict

Historian Chris Helmecke believes that Hitler massively underestimated his Soviet enemy: "There can be little doubt that the soldiers of the Red Army were doggedly determined. Their commanders were always learning new ways to do battle." The assumption was clearly that it would be possible to rout "the Soviet Union in a huge Blitzkrieg of encirclement battles close to the border between the two sides. There was no alternative plan for the possible failure of this concept." What is more, the Germany economy was not prepared for a long-term conflict, says Helmecke: "They simply didn't have the resources."

By the time of the German defeat in the Battle of Stalingrad that ended on 2 Februar 1943 at the very latest, it was clear that Hitler's aggressive war of occupation was falling apart. The Third Reich had overstretched itself by choosing to fight in a two-front war against both the western Allies and the Soviet Union. The failure of Operation Barbarossa is seen as the turning point in World War II. Helmecke concludes, "With hindsight, it is possible to say that the war was already strategically lost in 1941."

The Soviet Union paid a terrible price in the Great Patriotic War, suffering the heaviest losses of all the nations involved, with 27 million deaths, including 14 million civilians. In his memoirs, Russian author and journalist Ilya Ehrenburg (1891- 1967) wrote: "In our country, there was probably no table at which people gathered in the evening where they were not aware of an empty seat."

In Central and Eastern Europe, the after-effects can be felt to the present day: From the shifting of borders to the practice of remembrance. "In the post-Soviet states – by which I do not only mean the Russian Federation – the war is still very much a part of people's lives," says Jörg Morré, director of the German-Russian Museum in the Karlshorst district of Berlin. "All these traces of the past – that is the many who lost their lives, those who were deeply traumatized or wounded, and others who were displaced and after the war forced to live away from their homeland. All this has become part of family histories that are now entering their third, fourth or even fifth generation."

Reconciliation between individuals

Is such a thing as reconciliation even possible after such terrible suffering? Yes, says Jörg Morré. And sometimes that reconciliation can be entirely unconditional: "I find it astonishing. Especially on the level of individual encounters." Of course, the terrible stories from the past have not been forgotten. "And when we Germans start getting pro-active and roll out a discussion about the question of blame, they just say 'Get on with it!' But no demands are put on us. And that is why I say that the gesture of reconciliation really is unconditional – across every level of the state."

Of course, within the government it is said that, "we cannot forget," says the director of the Germany-Russian Museum. And this debate has sometimes also been linked with political demands: "But that is just one way of trying to take history and make contemporary political capital out of it."

This article has been translated from German.