Every major war of the 20th Century has produced heroes of the hour - men who rose above the mediocrity to lead their fellow soldiers to victory, or sometimes defeat. In Clash of Warriors, we examine the backgrounds and personalities of the finest commanders of that century. Each episode takes two of the worlds greatest combatants as they face their ultimate tests against each other.

Operation Citadel, Hitlers attempt to pinch out the Kursk salient, was his last great offensive on the Eastern Front. It became the greatest clash of armour the world had ever seen, and both armies knew that this was a pivotal battle of World War 2. If the German Panzer armies under Erich von Manstein - reinforced with the latest Tiger tanks - could break through, more than half a million Soviet troops would be cut off. If Nikolai Vatutins men could hurl them back, then a resurgent Red Army could seize the initiative for a series of relentless offensives.

The AIIied invasion of Europe on 6 June 1944 was the greatest all-arms combined operation in military history. Allied Supreme Commander, Dwight D Eisenhower, had an armada ol 6,000 ships, almost 1 million men, and a bewildering array of weapons and equipment for Operation Overlord. They faced a German enemy that was battle-hardened, formidable in defence, and commanded by one of the Wehrmacht's most experienced leaders, Gerd von Rundstedt. D-Day was a huge gamble, and its success or failure would decide the war in the West.