Historians probing the deep-seated psychological ills that motivated Adolf Hitler’s war on humanity have pointed to one very small but very crucial factor: his penis.

Funny as it may be to speculate about the Führer’s Untermensch, scientifically speaking, it’s probable that the allegations are true.

In their new book Hitler’s Last Day: Minute by Minute, historians Jonathan Mayo and Emma Craigie allege to have found medical records showing that the Führer had been diagnosed with a congenital condition called hypospadias, in which the urethra develops on the underbelly of the penis rather than at the tip.

In the most severe cases — Hitler apparently being a prime example — the penis turns out abnormally small and occasionally curves downward toward the floor, even when erect. Left untreated, the hypospadias-ridden adult man is likely to end up having a very messy bathroom floor and finding himself stuck in awkward sex positions, if he ever manages to overcome the psychological issues that come with it and seek out partners in the first place.

Mayo and Craig allege to have found records of Hitler’s diagnosis written up by his private physician, Theodor Morell. Whether or not the documentation is real, the allegations of his condition are entirely probable because, statistically, hypospadias occurs more often than we’d suspect. About 1.5 in every 10,000 American boys are diagnosed with a micropenis, which technically means having a stretched length of less than 3 inches. Likewise, hypospadias is a “common” condition in newborn boys, estimated to occur in up to 1 in every 200 boys.

These days, treatment is as simple as a simple surgery to reorient the urethra, but unfortunately for the Führer, these techniques weren’t developed in time to help him subvert any resulting psychological issues.

Speculation about the Führer’s lack of junk is nothing new: “Hitler Has Only Got One Ball,” a song about the Nazi leader’s undescended testicle, has been sung gleefully by schoolchildren and adults alike since British propagandists dropped the savage track in 1939. While rumors of Hitler’s cryptorchidism are also allegedly backed up by medical records, the condition is, like hypospadias, fairly common, occurring in two to four percent of newborn males.

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