Astrologically speaking, Hitler had a very unique and interesting combination of planets that specifically empowered his speech to a great degree. Having Pluto and Neptune in Gemini (the sign that Mercury, the planet of speech, rules) gave him an otherworldly, transformative, and intense way of speech. He also has a Golden Yod with the planets Neptune and Saturn at the base, and the Moon and Jupiter conjunct on the same degree in the 3rd house (the manner in which one communicates) at the apex. This intense aspect also gave him a profound speaking ability using emotions(Moon) and wisdom(Jupiter) to create extremely moving speeches.