The Wehrmacht was weakened by the loss of men and equipment in the battle of Stalingrad, but the army still could put more than three million troops in the field, and Hitler was eager to prove the German army was still formidable. After months of delay, Hitler decided to put his troops to the test in one great offensive that he said “will shine like a beacon around the world.”

Operation Citadel was aimed at eliminating the Red Army at Kursk. The town itself was of minor significance; it was chosen because it was situated in a bulge between the fronts of Field Marshal Erich von Manstein's Army Group South and Field Marshal Hans Gunther von Kluge's Army Group Center. Hitler believed the attack would destroy five Soviet armies and thereby prevent the Soviets from mounting any offensives for at least the remainder of the year. Success in battle would also allow Hitler to direct more resources to the Mediterranean theater.

Originally, the offensive was to quickly follow the successful recapture of Kharkov, but bad weather, indecision, and distractions on other fronts postponed the attack. When the Germans were finally ready to go, the Soviets had been given time to prepare. Approximately 570,000 German soldiers faced nearly one million Russians protected by more than 6,000 miles of trenches interspersed with an average of 2,400 antitank and 2,700 antipersonnel mines for each mile of front.

The German attack began on July 5 and moved steadily for four days before stiff resistance stopped it. The Russians counterattacked and began to reverse the German gains. Suddenly, Hitler called off Citadel to divert troops to meet the Allied forces that had just landed in Sicily.

What made the defeat particularly damaging to the German war effort was the loss of equipment. The fight for Kursk involved the largest tank battle in history, a total of 6,000 tanks, and the German loss of approximately 3,000 was devastating because new ones were not manufactured quickly enough to replace them. The air battle was equally fierce, with 4,000 aircraft in combat. The Germans bore the brunt, losing nearly 1,400.

The Russians were not about to give the Germans a break. On August 3, 1943, the Red Army attacked Kursk and overwhelmed the troops that had been on the attack a month earlier. The Germans were on the run. Ignoring pleas for reinforcements, Hitler instead ordered the creation of a fortified line, the East Wall — not to give his troops a place to fall back to and hold, but rather to prevent a retreat. German forces never again threatened Moscow and, from that point on, the Russians seized the initiative and did not let up until reaching Berlin.

Sources: Bard, Mitchell G. The Complete Idiot's Guide to World War II. 2nd Edition. NY: Alpha Books, 2004; The Simon Wiesenthal Center; The History Net

World War II: Operation Citadel