On 12 April 1945, the Supreme Commander of the Allied Forces Dwight D. Eisenhower visited Ohrdruf, south of Gotha. U.S. Army soldiers had reached the Buchenwald subcamp the previous week, shortly after its clearance, and come across hundreds of corpses and a few survivors. It was in Ohrdruf that they were first confronted directly with the crimes committed in the concentration camps. The future U.S. president and the men accompanying him were profoundly shocked and dismayed by what they saw.
Eisenhower later wrote: “I have never felt able to describe my emotional reactions when I first came face to face with indisputable evidence of Nazi brutality and ruthless disregard of every shred of decency. Up to that time I had known about it only generally or through secondary sources. I am certain, however, that I have never at any other time experienced an equal sense of shock.”
Source: Dwight D. Eisenhower, Crusade in Europe, Baltimore 1997.