This image, online via the U.S. National Archives and Records Administration (NARA), depicts a scene at the newly liberated Nazi concentration camp at Buchenwald. NARA describes the photo with these words: “WWII Europe: Germany: Concentration Camps: Piles of dead prisoners." The U.S. Holocaust Memorial Museum provides more detail: “German civilians under US military escort are forced to view a wagon piled with corpses in the newly liberated Buchenwald camp. Germany, April 16, 1945.”
World War II was documented by different types of primary source material: Photographs; audio/visual footage; documents; memoirs; eyewitness testimony.
Much of that evidence, maintained by the Library of Congress and the U.S. National Archives, has been digitized. Representative samples constitute "proof" that Hitler's regime planned the genocide.
Heinrich Himmler, one of Adolf Hitler's trusted insiders, was responsible for overseeing the "Final Solution" to the "Jewish problem." In a speech to one hundred SS generals (on October 4, 1943 in Posen, Poland), Himmler actually spoke about exterminating the Jews.
His handwritten note uses the phrase Judenevakuierung, or "evacuation of the Jews." However, the sound recording of his speech, maintained at the U.S. National Archives, reveals much more than his handwritten note.
Talking with the SS, Himmler actually defines what he means by the euphemism "evacuation." The official translation of Himmler's speech (Exhibit 1919-PS from the Nuremberg War Crime Trials) states in English what the Third Reich intended to do with the Jews of Europe: Exterminate them.
Eyewitness accounts, from many survivors, tell a gruesome tale of extraordinary cruelty and suffering (such as the events at Babi Yar in September, 1941). But the photographic evidence nearly defies belief.
As Hitler's regime crumbled in the face of the Allied advance, Nazis tried to destroy evidence of what they had done to other human beings. What they left behind will forever haunt those who study these primary-source materials.