After their loss in the Battle of Stalingrad, the Nazis decided to focus on a new target: Kursk. They called the plan to attack Kursk Operation Citadel, and chose to attack in summer, since they always lost during the bitter Russian winter.
The battle had been planned for early summer, but the Nazis had to wait for new tanks and other supplies to arrive. This gave the Russians (Red Army) lots of time to prepare.
Defenses in Italy are low, send more soldiers there
To prepare, the Red Army dug trenches designed to stop German tanks. By July, when the battle started, the Red Army had 1.3 million troops, 2,800 planes, and 3,600 tanks. The Germans had 900,000 troops, 2,000 planes, and 2,700 tanks.
Red Army declares victory
The Germans attacked first, but the Red Army was able to hold them off, then counterattacked. The Soviets were than able to take back the Russian cities of Orel and Karkhov.
At the same time, the Allies started taking back Western Europe. Hitler started sending new troops to Sicily, where Allied troops had landed days after the Battle of Kursk had started. A week later, Operation Citadel was cancelled. Troops already in Kursk were unable to retreat.
The Red Army were victorious. The Nazis lost about 56,000 soldiers, and the Soviets has lost about 250,000 soldiers.