Winston Churchill called him “the noblest Roman”; President Harry Truman said he was “the greatest military man America ever produced”; and U.S. Secretary of War Henry L. Stimson considered Marshall the finest soldier he had ever known.

In 1939 General George C. Marshall became U.S. Army Chief of Staff–the highest rank in the Army. The day of his promotion, however, would prove prophetic: Hitler invaded Poland, and Marshall’s work was cut out for him.

While Americans watched the advance of Hitler across Europe with horror, Marshall began to prepare for what he believed was inevitable armed conflict. By the time the United States went to war in 1941, Marshall’s leadership, foresight, and integrity had led to the expansion of the Army from 172,000 men to more than a million. By early 1945, the Army had grown to more than eight million – an achievement that required brilliant planning, persuasion, and execution skills.

Throughout World War II, Marshall was at the heart of solving many problems – strategy, supply, budgeting, leadership, and battle priority. Most important was Marshall’s role in the outcome of the war: the Allied Victory.

By March 1942, Marshall was firming up the concept to consolidate the Allied armies and use that amazing force to defeat the Germans. His plan was to build a huge U.S. army, ship it to England, cross the Channel, and invade France. Ultimately, the execution of the plan was stalled many times over, much to the concern of Marshall, and required 90 separate meetings before being launched in 1944. But what Marshall predicted then we know today: Normandy proved that the power of a coordinated, worldwide Allied strategy was the way to win the war.

As U.S. Army Chief of Staff, General George C. Marshall was indispensable. He negotiated wartime strategy alongside President Roosevelt, Winston Churchill, and Joseph Stalin, and he was responsible for the smooth operation of the Alliance and the execution of the Normandy Invasion. His counsel and leadership also played a key role in the defeat of Japan in 1945.