Operation Bagration was the codename of the Soviet offensive against the German Army Group Center in the summer of 1944, resulting in the liberation of most of the Soviet Union's territory.
In June 1944, while the Western Allies landed in Normandy, the Red Army was preparing a major offensive in Belarus. The Soviets had conducted a successful campaign of deception, termed maskirovka in Russian, concealing the buildup of forces in the center, while inducing to the Germans the idea that the main attack will be in Ukraine. A major Soviet offensive, known as Lvov-Sandomierz offensive, would take place indeed in Ukraine, but a few weeks later. Before the start of the offensive in Belarus, Soviet partisans put explosive charges on the railway lines, disrupting the German transport of troops and supplies.
The German Army Group Center, having few mobile reserves, had organized a rather fixed defense around the so-called Feste Plätze - fortified places. On the other hand, the Red Army had a categorical numerical superiority throughout the battle, especially in tanks (including assault guns) and aircraft.
The Soviet plan was to perform a double envelopment, aiming to encircle as much as possible of German Army Group Center. The Soviets had powerful mechanized and armored reserves, ready to exploit in deep the penetrations in the enemy front.
On June 22, 1944, the Soviet offensive began with probing attacks, followed the next day by a powerful artillery bombardment. In the northern sector, the 1st Baltic Front and 3rd Belorussian Front penetrated the German lines, encircling an entire German army corps around the city of Vitebsk. In the southern sector, the 1st Belorussian Front surrounded two German corps east of Bobruisk.
By early July, the Red Army had caught the Army Group Center in a huge pincer movement around Minsk, destroying much of it. Whereas the German defense collapsed, the Soviets continued their offensive until mid-August, entering the Baltic states and Eastern Poland, up to the Vistula river.
The Soviet Belorussian strategic offensive operation had devastating effects for the Germans, the losses being much like those suffered in the Battle of Stalingrad. Also in the summer of 1944, Nazi Germany received another major blow losing the Battle of Normandy in face of the Western Allies.