Operation Barbarossa, 1941. Part 4.

On June 22, 1941, Nazi Germany and its Axis allies began a massive invasion of the Soviet Union named Operation Barbarossa — some 4.5 million troops launched a surprise attack deployed from German-controlled Poland, Finland, and Romania. Hitler had long had his eye on Soviet resources. Although Germany had signed a non-aggression pact with the USSR in 1939, both sides remained suspicious of one another, and the agreement merely gave them more time to prepare for a probable war.

A Finnish troop train passes through a scene of an earlier explosion which wrecked one train, tearing up the rails and embankment, on October 19, 1941.

A Finnish troop train passes through a scene of an earlier explosion which wrecked one train, tearing up the rails and embankment, on October 19, 1941.

A German half-track driver inside an armored vehicle in Russia in August of 1941.

A German half-track driver inside an armored vehicle in Russia in August of 1941.

A huge Russian gun on tracks, likely a 203 mm howitzer M1931, is manned by its crew in a well-concealed position on the Russian front on September 15, 1941.

A huge Russian gun on tracks, likely a 203 mm howitzer M1931, is manned by its crew in a well-concealed position on the Russian front on September 15, 1941.

Evidence of Soviet resistance in the streets of Rostov, a scene in late 1941, encountered by the Germans as they entered the heavily besieged city.

Evidence of Soviet resistance in the streets of Rostov, a scene in late 1941, encountered by the Germans as they entered the heavily besieged city.

Finnish soldiers storm a soviet bunker on August 10, 1941. One of the Soviet bunker's crew surrenders, left.

Finnish soldiers storm a soviet bunker on August 10, 1941. One of the Soviet bunker’s crew surrenders, left.

Five Soviet civilians on a platform, with nooses around their necks, about to be hanged by German soldiers, near the town of Velizh in the Smolensk region, in September of 1941.

Five Soviet civilians on a platform, with nooses around their necks, about to be hanged by German soldiers, near the town of Velizh in the Smolensk region, in September of 1941.

German Army Commander Colonel General Ernst Busch inspects an anti-aircraft gun position, somewhere in Germany, on Sept. 3, 1941.

German Army Commander Colonel General Ernst Busch inspects an anti-aircraft gun position, somewhere in Germany, on Sept. 3, 1941.

German infantrymen force their way into a snipers hide-out, where Russians had been firing upon advancing German troops, on September 1, 1941.

German infantrymen force their way into a snipers hide-out, where Russians had been firing upon advancing German troops, on September 1, 1941.

German soldiers move a horse-drawn vehicle over a corduroy road while crossing a wetland area, in October 1941, near Salla on Kola Peninsula, a Soviet-occupied region in northeast Finland.

German soldiers move a horse-drawn vehicle over a corduroy road while crossing a wetland area, in October 1941, near Salla on Kola Peninsula, a Soviet-occupied region in northeast Finland.

German soldiers, supported by armored personnel carriers, move into a burning Russian village at an unknown location during the German invasion of the Soviet Union, on June 26, 1941.

German soldiers, supported by armored personnel carriers, move into a burning Russian village at an unknown location during the German invasion of the Soviet Union, on June 26, 1941.

German troops make a hasty advance through a blazing Leningrad suburb, in Russia on November 24, 1941.

German troops make a hasty advance through a blazing Leningrad suburb, in Russia on November 24, 1941.

Nazi troops lie concealed in the undergrowth during the fighting prior to the capture of Kiev, Ukraine, in 1941.

Nazi troops lie concealed in the undergrowth during the fighting prior to the capture of Kiev, Ukraine, in 1941.

Rapidly advancing German forces encountered serious guerrilla resistance behind their front lines. Here, four guerrillas with fixed bayonets and a small machine gun are seen in action, near a small village.

Rapidly advancing German forces encountered serious guerrilla resistance behind their front lines. Here, four guerrillas with fixed bayonets and a small machine gun are seen in action, near a small village.

Russian men and women rescue their humble belongings from their burning homes, said to have been set on fire by the Russians, part of a scorched-earth policy, in a Leningrad suburb on October 21, 1941.

Russian men and women rescue their humble belongings from their burning homes, said to have been set on fire by the Russians, part of a scorched-earth policy, in a Leningrad suburb on October 21, 1941.

More information and photos you can find in our previous post.