Walter Karl Ernst August von Reichenau (8 October 1884 – 17 January 1942) was a field marshal in the Wehrmacht of Germany during World War II.
A professional soldier and veteran of World War I and the Reichswehr, he was one of twelve officers promoted at the 1940 Field Marshal Ceremony, and the most junior. Although regarded by contemporaries and historians as one of Germany's most competent military officers, it was his early political affiliation with the NS political apparatus which was key to his rapid rise, something resented by many older and more senior officers in the Army. This resentment was a factor in his twice being denied promotion to head the Army, despite Hitler's support.
An avid sportsman and athlete he was a member of the International Olympic Committee.
He is widely cited for his Severity Order which he issued while in command of the German 6th Army.