In 1941 Leningrad (St. Petersburg) was the second largest city in the Soviet Union. On September 8, 1941 it was attacked by German and Finnish troops. The 872 day seige of Stalingrad resulted in the loss of more than one million of the city's Red Army defenders and citizens.
At the time of the attack more than 2 million people remained in the city. Stalingrad was nearly surrounded in short order by the Finns and Germans (side note -- why are not the Finns view in the same light as the Vichy French?) except for the shores of Lake Ladoga. All able bodied people in the city, including children and women were put to work building defensive works and anti-tank fortifications. On the first day of the seige an aerial attack by the Axis set fire to the warehouse district, destroying much of the available food.
By December the food supply was exhausted. The animals from the zoo and almost all of the pets in the city had been eaten. Rations were down to 125 gram of bread (about one slice = about 4 ounces). Temperatures fell to around -40 F, one of the coldest winters in decades. Inhabitants burned books and furniture for warmth, they ate wallpaper paste and boiled shoe leather. Grass and weeds were cooked. Cannibalism became rampant. A few supplies were smuggled across Lake Ladoga.
The seige wore on. Air attacks continued. More than 600,000 died in the year of 1942. The Leningrad Police formed a special unit to combat cannibalism. The German air attacks were relentless. Barges braved the air attacks to just keep the city alive. By January 1943 the Red Army boke through the lines widening the lanes to the Lake. Finally in January 1944 the Red Army approached Leningrad, forcing the German Army to retreat. On January 27, 1944 the seige was over.
More than one million Soviets died during the seige of Leningrad. It would take more than 20 years for the city to reach again its prewar population of 3 million.