The greatest movement of men and arms began on the morning of June 22, 1941, when slightly more than 3 million German troops invaded the USSR. Although German preparations had been visible for months and had been talked about openly among the diplomats in Moscow, the Soviet forces were taken by surprise. Stalin, his confidence in the country's military capability shaken by the Finnish war, had refused to allow any counteractivity for fear of provoking the Germans. Moreover, the Soviet military leadership had concluded that blitzkrieg, as it had been practiced in Poland and France, would not be possible on the scale of a Soviet-German war; both sides would therefore confine themselves for the first several weeks at least to sparring along the frontier. The Soviet army had 2.9 million troops on the western border and outnumbered the Germans by two to one in tanks and by two or three to one in aircraft. Many of its tanks and aircraft were older types, but some of the tanks, particularly the later famous T-34s, were far superior to any the Germans had. Large numbers of the aircraft were destroyed on the ground in the first day, however, and their tanks, like those of the French, were scattered among the infantry, where they could not be effective against the German panzer groups. The infantry was first ordered to counterattack, which was impossible, and then forbidden to retreat, which ensured their wholesale destruction or capture.Originally Posted by Adolf Hitler
Hitler at his Fuhrer Headquarters
In preparation for the attack, Hitler moved 3.2 million German soldiers and about 1 million Axis soldiers to the Soviet border, launched many aerial surveillance missions over Soviet territory, and stockpiled materiel in the East. The Soviets were still taken by surprise, mostly due to Stalin's belief that the Third Reich was unlikely to attack only two years after signing the Molotov-Ribbentrop Pact. The Soviet leader also believed that the Nazis would likely finish their war with Britain before opening a new front. He refused to believe repeated warnings from his intelligence services on the Nazi buildup, fearing the reports to be British misinformation designed to spark a war between the Nazis and the USSR. The German government also aided in this deception, telling Stalin that the troops were being moved to take them out of range of British bombers. The Germans also explained that they were trying to trick the British into thinking they were planning to attack the Soviet Union, while in fact the troops and supplies were being stockpiled for an invasion of Britain. As a result, Stalin's preparations against a possible German invasion in 1941 were half-hearted. The spy Dr. Richard Sorge gave Stalin the exact German launch date; Swedish cryptanalysts led by Arne Beurling also knew the date beforehand.
The Germans set up deception operations, from April 1941, to add substance to their claims that Britain was the real target: Operations Haifisch and Harpune. These simulated preparations in Norway, the Channel coast and Britain. There were supporting activities such as ship concentrations, reconnaissance flights and training exercises. Invasion plans were developed and some details were allowed to leak.
Hitler also researched into Napoleon's disastrous invasion of Russia. At Hitler's insistence, the German High Command (OKW) began to develop a strategy to avoid repeating these mistakes. The strategy Hitler and his generals agreed upon involved three separate army groups assigned to capture specific regions and cities of the Soviet Union. The main German thrusts were conducted along historical invasion routes. Army Group North was assigned to march through the Baltics, into northern Russia, and either take or destroy the city of Leningrad (now Saint Petersburg). Army Group Center would advance to Smolensk and then Moscow, marching through what is now Belarus and the west-central regions of Russia proper. Army Group South was to strike the heavily populated and agricultural heartland of Ukraine, taking Kiev before continuing eastward over the steppes of southern Russia all the way to the Volga and the oil-rich Caucasus.
Hitler, the OKW and the various high commands disagreed about what the main objectives should be. In the preparation for Barbarossa, most of the OKW argued for a straight thrust to Moscow, whereas Hitler kept asserting his intention to seize the resource-rich Ukraine and Baltics before concentrating on Moscow. An initial delay, which postponed the start of Barbarossa from mid-May to the end of June 1941, may have been insignificant, especially since the Russian muddy season came late that year. However, more time was lost at various critical moments as Hitler and the OKW suspended operations in order to argue about strategic objectives.
OKW plans for the invasion of the Soviet Union
Originally Posted by Adolf Hitler
A German squad attacking on the first shots of Barbarossa
Intro sourced from Wikipedia and History Channel. Everything below this line is originally written