For a bunch of amoral foul-ups, the Nazis at Nuremberg were an above average group. Four of them, Schacht, Seyss-Inquart, Göring and Dönitz were in the genius range. In fact, Schacht and Seyss-Inquart possessed IQ's equaled by a mere 1 percent of humanity. Unfortunately, Hitler himself was never tested (though some have attempted to estimate his IQ), leading to much speculation about his relative intelligence.
During the course of the defendants' testimony during the trial of the major war criminals, many of them offered their reflections on Hitler; truly informed opinions which provide a number of clues to the Führer's intellectual capacity. (Note: One must, of course, bear in mind that the defendants continually emphasized Hitlers unassailable authority as an element in their defense, saying in effect that the Führer was the whole show and they had little or no influence, thereby mitigating their own guilt.) The following are some pertinent excerpts from this fascinating material:
(...)
Some maintain that Hitler was not an 'original thinker,' thus denying that his IQ was much more than 140 or so. I am of the opinion that Hitler WAS an original thinker. This is based on the obvious innovations Hitler created in the fields of armored warfare and propaganda, as well as his compelling-to-Germans-of his-time synthesis of the major ideas of his day (Social Darwinism, nationalism, socialism, capitalism, etc.) into a workable ideology.
My best guess was that Hitler's IQ was around 150.
(...)