Second World War: A decisive Soviet victory against German forces at the Battle of Kursk gave the Red Army the strategic initiative for the rest of the war.

World War II or the Second World War was a global conflict between two coalitions: the Allies and the Axis powers. Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks and aircraft played major roles, enabling the strategic bombing of cities and delivery of the first and only nuclear weapons ever used in war. World War II is the deadliest conflict in history, causing the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Germany, Austria, Japan, and Korea were occupied, and German and Japanese leaders were tried for war crimes.

The Battle of Kursk, also called the Battle of the Kursk Salient, was a major World War II Eastern Front battle between the forces of Nazi Germany and the Soviet Union near Kursk in southwestern Russia during the summer of 1943, resulting in a Soviet victory. The Battle of Kursk is the single largest battle in the history of warfare. It ranks only behind the Battle of Stalingrad several months earlier as the most often-cited turning point in the European theatre of the war. It was one of the costliest battles of the Second World War, the single deadliest armoured battle in history, and the opening day of the battle, 5 July, was the single costliest day in the history of aerial warfare in terms of aircraft shot down. The battle was further marked by fierce house-to-house fighting and hand-to-hand combat.

The Workers' and Peasants' Red Army, often shortened to the Red Army, was the army and air force of the Russian Soviet Republic and, from 1922, the Soviet Union. The army was established in January 1918 by a decree of the Council of People's Commissars to oppose the military forces of the new nation's adversaries during the Russian Civil War, especially the various groups collectively known as the White Army. In February 1946, the Red Army was renamed the "Soviet Army". Following the dissolution of the Soviet Union it was split between the post-Soviet states, with its bulk becoming the Russian Ground Forces, commonly considered to be the successor of the Soviet Army.