On June 22nd shortly past three a.m. Nazi troops invaded the Soviet territory without a declaration of war. The Nazis had 4.6 million men, 190 divisions, more than 4 thousand tanks, over 47 thousand guns and mortars, about 5 thousand aircraft and up to 200 ships. Soviet forces had 2 million 680 thousand men, 37.5 thousand guns and mortars, 1475 new tanks, 1540 new combat aircraft and a considerable number of older tanks and planes. In some areas the aggressor outnumbered Soviet troops by 3 or 4 times. On the first day of the war Soviet troops retreated up to 50 kilometers in some places, Soviet aviation lost about 1200 planes.

In the first three weeks German troops advanced 20 or 30 kilometers daily into the Soviet territory. The first blow was taken by frontier guards, who were severely decimated by the advancing Nazi forces. The country will never forget heroism of the defenders of the Brest Fortress who held out for about a month. In appreciation of the mass heroism and courage of its residents the city of Brest was made Hero City. By mid-July the German troops occupied Latvia, Lithuania, Western Ukraine, Belorussia. In appreciation for the mass heroism of its residents the capital of Belorussia - Minsk was made Hero City too.

Early in August the Germans were advancing in three directions. In the north they were determined to seize Leningrad. In the central direction their purpose was to destroy the country's capital Moscow. In the south-east the German command planned to occupy Ukraine, the Crimean peninsula and enter the Caucasus. In a short period of time German troops advanced 400 to 500 kilometers in the north-west, 450 to 600 kilometers in the west and 300 to 350 kilometers in the south-west.

On July 10th the Germans began their offensive on the Leningrad front. German troops were gradually tightening the siege of Leningrad. Late in August all railway routes connecting Leningrad with the country were cut off. Communication links with the city could only be maintained across the Ladoga Lake or by air. On September 8th land communication with Leningrad stopped and the 900-day siege of the city began. In September one of the fiercest air raids against Leningrad took place with the participation of 276 planes. The city suffered 6 bombardments all in one day. On November 20th the besieged residents of Leningrad began starving. The siege lasted until January In appreciation for the mass heroism of its defenders Leningrad was made Hero City.

July 10th marked the beginning of the offensive against Moscow where the German command concentrated half of its manpower, one third of artillery pieces and 75% of tanks of the total number of manpower and hardware on the Soviet-German front. On the way to Moscow was the city of Smolensk. By December 25th the threat of Moscow being encircled from the north and south had been removed. The Battle of Moscow lasted until April 20th, In appreciation of the mass heroism of its residents Moscow was made Hero City. More than 3 million people, up to 3 thousand tanks, more than 2 thousand planes and over 22 thousand guns and mortars were involved in the battle on both sides.

The Battle of Stalingrad began on July 17th. It covered 100 thousand square kilometers and lasted 200 days. More than 2 million people took part in the battle from both sides. By mid-November German troops had seized most of the city. In two parts of the city they had reached the Volga but failed to cross it. On November 11 German troops made the last attempt to capture Stalingrad. November 19th through February 2nd the next year marked a counter-offensive of the Soviet troops on the Stalingrad front. As a result, the German army was encircled. Enemy losses in the Battle of Stalingrad totaled 1.5 million people.