Although the threat of conflict had loomed since the early 1930s. Germany and the USSR launched a joint war against Poland in September of 1939, which the Soviets followed up with invasions of Finland, Romania, and the Baltic states across the following year.
After Germany crushed France, and determined that it could not easily drive Great Britain from the war, the Wehrmacht turned its attention back to the East. Following the conquests of Greece and Yugolavia in the spring of 1941, Berlin prepared its most ambitious campaign; the destruction of Soviet Russia. The ensuing war would result in a staggering loss of human life, and in the final destruction of the Nazi regime.
The Fight on Land:
On June 22, 1941, the German Wehrmacht and Luftwaffe struck Soviet forces across a wide front along the German-Soviet frontier. Romanian forces attacked into Soviet-occupied Bessarabia on the same day. The Finnish armed forces joined the fight later that week, with Hungarian troops and aircraft entering combat at the beginning of July. By that time, a significant contribution of Italian troops was on its way to the Eastern Front. A Spanish volunteer division would eventually join the fight, along with large formations recruited from Soviet prisoners of war and from the local civilian population of occupied Soviet territories.
The course of the war is far too complicated to detail in this article. Suffice to say that the German enjoyed overwhelming success for the first five months of the war, before weather and stiffening Red Army resistance led to a Soviet victory in the Battle of Moscow. Germany resumed the offensive in 1942, only to suffer a major defeat at Stalingrad. The Battle of Kursk, in 1943, ended the Wehrmacht’s offensive ambitions. 1943, 1944, and 1945 saw the pace of Soviet conquest gradually accelerate, with the monumental offensives of late 1944 shattering the German armed forces. The war turned the Wehrmacht and the Red Army into finely honed fighting machines, while also draining both of equipment and manpower. The Soviets enjoyed the support of Western industry, while the Germans relied on the resources of occupied Europe.
The Fight in the Air:
Mercifully, the nature of the war did not offer many opportunities for strategic bombing. Russia launched a few sorties against German cities in the first days of the war, usually suffering catastrophic casualties. For their part, the German Luftwaffe concentrated on tactical support of the Wehrmacht. Germany did launch a few large air raids against Russian cities, but did not maintain anything approaching a strategic campaign.
Notwithstanding the improvement of the Soviet Air Force across the war, and the effectiveness in particular of attack aircraft, in general the Luftwaffe mauled its Soviet foe. This remained the case even as the Soviet aviation industry far outstripped the German, and as the Combined Bomber Offensive drew the attention of the Luftwaffe to the west.
The Fight at Sea:
Naval combat does not normally loom large in histories of the War in the East. Nevertheless, Soviet and Axis forces fought in the Arctic, the Baltic, and the Black Sea for most of the conflict. In the north, Soviet air and naval forces supported convoys from the Western allies to Murmansk, and harassed German positions in Norway. In the Black Sea, German and Romanian ships struggled against the Soviet Black Sea Fleet, winning important victories until the tide of the land battle turned. In the Baltic, Russian submarines and small craft fought a guerilla conflict against Germany and Finland for the first three years, although the Germans successfully leveraged their surface naval superiority in support of retreats in the final year of the war.
The Fight Against Civilians:
The Holocaust is perhaps the most remembered legacy of the War in the East. The invasions of Poland and the Soviet Union brought the bulk of Eastern Europe’s Jewish population under Nazi control, facilitating a German policy of extermination. For non-Jews, German occupation policies were nearly as brutal, although populations sympathetic to the anti-Soviet crusade were sometimes spared.
Towards the end of the war, the Soviets did their best to return the favor. Soviet depredations against the German civilian population of East and Central Europe do not generally received the same degree of attention as German actions, in no small part because of an enduring (if problematic) sense that the German deserved what they got. Other Eastern European populations were caught in the crossfire, suffering starvation and other depredations from both sides. Nevertheless, there is no question that the Soviets (and the peoples of Eastern Europe) suffered far more deeply from the war than the Germans.
The raw statistics of the war are nothing short of stunning. On the Soviet side, some seven million soldiers died in action, with another 3.6 million dying in German POW camps. The Germans lost four million soldiers in action, and another 370000 to the Soviet camp system. Some 600000 soldiers from other participants (mostly Eastern European) died as well. These numbers do not include soldiers lost on either side of the German-Polish War, or the Russo-Finnish War.
The civilian population of the territory in conflict suffered terribly from the war, in part because of the horrific occupation policies of the German (and the Soviets), and in part because of a lack of food and other necessities of life. Around 15 million Soviet civilians are thought to have been killed. Some three million ethnic Poles died (some before the German invasion of the Soviet Union, but many after) along with around three million Jews of Polish and another two million of Soviet citizenship (included in the Soviet statistics). Somewhere between 500000 and 2 million German civilians died in the expulsions that followed the war.
Statistics of this magnitude are inevitably imprecise, and scholars on all sides of the war continue to debate the size of military and civilian losses. There is little question, however, that the War in the East was the most brutal conflict ever endured by humankind. There is also little question that the Red Army provided the most decisive blows against Nazi Germany, causing the vast majority of German casualties during World War II as a whole.
The end of the War in the East left the Soviet Union in control of a vast portion of the Eurasian continent. Red Army forces occupied Germany, Poland, Czechosolvakia, parts of the Balkans, the Baltic states, and parts of Finland. The Western allies remained in control of Greece and much of western Germany, while Joseph Tito established an independent communist regime in Yugoslavia. The Soviet Union redrew the map of Eastern Europe, annexing large chunks of Poland, Germany, and the Baltics, and ceding much of Germany to Polish control. Russian domination over the region would last into the early 1990s, when the layers of the Soviet Empire began to peel away.
The scars of the war remain, not least in the absence of the populations exterminated during the conflict. The states occupied by the Soviet Union at the end of the war (including Poland, the Baltics, and Ukraine) remain deeply suspicious of Russian intentions. For its part, memory of the war in Russia continues to condition Russian foreign policy, and Russia’s broader response to Europe.
Robert Farley is a frequent contributor to TNI, is author of The Battleship Book . He serves as an Senior Lecturer at the Patterson School of Diplomacy and International Commerce at the University of Kentucky. His work includes military doctrine, national security, and maritime affairs. He blogs at Lawyers, Guns and Money  and Information Dissemination  and The Diplomat .
This first appeared in October 2015 and is being reposted due to reader interest.