All existing evidence points to Libra rising and it is certainly within reason and probably true. Libra is a cardinal masculine sign and Hitler was certainly initiating not at all fixed like Scorpio. With Libra rising his ASC ruler Venus is horribly afflicted. It is in Taurus, her domicile, but she is retrograde, conjunct Mars in Taurus (detriment) and square Saturn in Leo (detriment). This is possibly the worst ASC ruler I've ever seen.
Several German astrologers claimed to have his accurate birth time but no definitive record exists. This is not unusual for the era in which he was born. Hitler, despite the myth, did not use or have much use for astrologers. He had more than a few sent to concentration camps. His henchmen did use astrology for propaganda purposes, and this is not the only time in history this was done. There is a strong possibility he didn't know his exact birth time.
Signs are neither good nor evil. Libra isn't always good and Scorpio always bad. Hitler supposedly loved children - well some children.
Fiery baseball player and manager Billy Martin had Libra rising. And if anyone is ever tempted to stick to the stereotypes, remember this: Playboy Magazine founder publisher and proponent of "The Playboy Lifestyle of easy sex, Hugh Hefner, has Virgo rising.
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" ... we will use the time of German astrologer Wilhelm Wulff. Wulff was a contemporary of Hitler and for man years was compelled to work under the direct orders of the Man in Chief of the SS - Heinrich Himler. It is reasonable that this time is most reliable. Wulf survived the war and wrote later his autobiographical book "The Zodiac and the Swastika" where he published the horoscopes of the Nazi leadership."
[Wulf can be Googled and the above mentioned book is online in various places ]
His data for Hitler is 1889, 20 April 17h 56m local time (i.e. LMT) Braunau, (Austria)" -- "Primary Directions I Rumen Kolev self published. Kolev is a recognized authority on Primary directions. That is he is recognized by people who know what they are talking about.
This gives 20 Libra 23 rising. The most common time used by astrologers for Hitler's birth is 6:30 PM LMT. Frank Clifford, noted birth researcher based in the UK, citing a baptismal certificate claims 6:30 PM which gives and ASC of 26 Libra 41.
If anyone has any documentation of a later time or even someone quoting other documentation, I've never seen it. I've seen new age nitwits use Scorpio rising without citing a source. It is up to those Scorpio rising people to produce something other than sun sign nonsense.