Fortunately, uniquely for the elites of a major state, we have some detailed data on the IQs of the Nazi leadership (with the exception of a few important guys like Goebbels, Himmler, Bormann, and the Fuhrer himself) thanks to the US psychometrists attached to Nuremberg.
1 Hjalmar Schacht 143
2 Arthur Seyss-Inquart 141
3 Hermann Goering 138
4 Karl Doenitz 138
5 Franz von Papen 134
6 Eric Raeder 134
7 Dr. Hans Frank 130
8 Hans Fritsche 130
9 Baldur von Schirach 130
10 Joachim von Ribbentrop 129
11 Wilhelm Keitel 129
12 Albert Speer 128
13 Alfred Jodl 127
14 Alfred Rosenberg 127
15 Constantin von Neurath 125
16 Walther Funk 124
17 Wilhelm Frick 124
18 Rudolf Hess 120
19 Fritz Sauckel 118
20 Ernst Kaltenbrunner 113
21 Julius Streicher 106
As I recall from what I’ve read on Hitler and internal Nazi politics, of the above list, particularly “close associates” of Hitler would include: Goering; Ribbentrop; Speer; and until his “betrayal,” Hess. Their average IQ is 129.
While there was never much love lost between Hitler and the German military establishment, the closest military connection to Hitler from that list would be Keitel, who was infamous for his toadying behavior towards the Fuhrer. His IQ also happened to be precisely 129.
(Incidentally, while Jodl is regarded as far more competent than Keitel – he is the guy who actually made OKW command structure run – it’s interesting to note his IQ was actually lower than that of his boss, if marginally so).
In practice, Goering’s IQ during his time as Nazi bigwig might have actually been lower, due to his morphine addiction. On the other hand, there are suspicions that Speer was in fact considerably cleverer than his test scores indicated, because he was playing the “dumb dreamer architect” type so as to pretend ignorance of the death camps and avoid execution (if so he was successful). So these two factors might cancel out.
Adjusting for the Flynn effect – but only modestly, since the most useful (not rules-dependent) forms of intelligence haven’t improved all that radically, and we have an IQ of around 125 for Hitler normed to today’s Greenwich standards.
I think this is essentially accurate. He was a high school dropout and failed to get into the Viennese Academy of Fine Arts. He was a brilliant orator, but oratory skills have low g loadings.
Hitler did write a famous book. But Mein Kampf is a very badly written book, even ideology outside. Here is one particularly egregious example that I still recall reading a dozen years later by virtue of just how bad it was:
THE EXTENT of the fall of a body is always measured by the distance between its momentary position and the one it originally occupied. The same is true of nations and states. A decisive significance must be ascribed to their previous position or rather elevation. Only what is accustomed to rise above the common limit can fall and crash to a manifest low This is what makes the collapse of the Reich so hard and terrible for every thinking and feeling man, since it brought a crash from heights which today, in view of the depths of our present degradation, are scarcely conceivable.
And this was after Hess – with an IQ of 120 – had labored on Mein Kampf long and hard to make it at least minimally suitable for publication.
On the other hand, Hitler was always near the top of his class academically, which puts a lower limit of about 120 on his IQ. Here is is a quote from a book b y a childhood friend of Hitler’s via Pumpkin Person:
From school sources there is abundant authentic material describing his school performance. In primary school he was always near the top of the class. He learned quickly and made good progress without much effort.
He was also a good but not brilliant artist. On the basis of this, Pumpkin Person estimates his Performance IQ at 133 (Flynn-adjusted).
Hitler has some major geopolitical successes early on, but these were probably more a result of aggression and blind luck than intelligence (had France decisively reacted anytime at Munich or beforehand, the Nazis would have been finished. Not even necessarily due to the allies. The generals were interminably planning a coup throughout the 1930s, to be put into action should Hitler’s plans have blown up).
These geopolitical victories were in any case completely reversed later on – thanks in significant part to Hitler refusing to listen to and heed the advice of his generals (in contrast, Stalin realized he was hopeless on military matters after 1941, and with a few costly exceptions like the Third Battle of Kharkov, largely left the technical details to his generals thereafter).
Against that, it should be admitted that the Nazi leadership was more or less uniformly of the opinion that Hitler had a very high intellect, and was possibly a genius. Apparently, this included Hjalmar Schacht, the brightest of them all:
He read an enormous amount and acquired a wide knowledge. He juggled with that knowledge in a masterly manner in all debates, discussions and speeches. He was undoubtedly a man of genius in certain respects. He had sudden ideas of which nobody else had thought and which were at times useful in solving great difficulties, sometimes with astounding simplicity, sometimes, however, with equally astounding brutality. He was a mass psychologist of really diabolical genius…
However, there are two potential confounds here. First of all, Hitler was a brilliant orator, which expressed itself not only in his speeches but his casual “table talk.” Even very intelligent people can easily mistake this for genius, especially if they are lacking in the rhetorical/charismatic department themselves. Second, the Nazis at Nuremburg had a vested interest in presenting Hitler as a “diabolical genius” type of character in order to diminish their own share of responsibility for war crimes (and their risk of being hanged).
My (very rough) impressions/recollections from reading Nazi histories is that Hitler was certainly a step above the likes of feckless-schoolboy type Hess or the infamously callous Kaltenbrunner, but decidedly below Franz von Papen, Doenitz, and Schacht. To the contrary, his intellectual ability seems to fit right in besides that of Speer and Ribbentrop (also personal friends), and of Rosenberg (the Nazi “philosopher”).
Finally, the 125 estimate for Hitler’s IQ broadly tallies with Pumpkin Person’s estimates of a verbal IQ of 120 and a Performance IQ of 133. Hence, I think it is credible.