Shostakovich gave the symphony its title because it is about what was happening in Leningrad in 1941. It was during the World War II and the German army had invaded the Soviet Union and blocked communication between the city of Leningrad (now called St Petersburg) and the rest of the world. Conditions were terrible: the people hardly had any food to eat and they were very cold in the winter. About a million people died during the siege. 