At Donald Trump's post-inauguration rally on sex scenes in video games videosMonday, presidential adviser, DOGE head and world’s richest human Elon Musk twice made a gesture that many identify with a "seig heil," the infamous Nazi salute.

The X, Tesla and SpaceX CEO thanked the assembled crowd saying, “I just want to say thank you for making it happen,” before biting his lip, dramatically slapping his chest with his right hand and sending his right arm skyward, palm out. Musk turned around and made the gesture again, adding, “My heart goes out to you. It is thanks to you that the future of civilization is assured.”

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As Senator Chris Murphy (D-Conn.) laid out during Tuesday's confirmation hearings for Trump’s future UN ambassador, it wasn’t just left-wing activists and anti-Musk figures who considered the gesture an ode to the genocidal German leader: “Evan Kilgore, a right-wing political commentator, wrote on X, Holy crap, did Elon Musk just heil Hitler at the Trump inauguration rally? This is incredible. We are so back'…the Proud Boys chapter in Ohio posted the clip on a Telegram channel with the text, ‘Heil Trump.’ A chapter of the white nationalist group White Lives Matter posted it on Telegram, ‘Thanks for hearing us, Elon. The white flame will rise again.”

For his part, Musk — who recently voiced support for far-right political parties in both the U.K. and Germany — wrote on X that "The ‘everyone is Hitler’ attack is sooo tired." He followed that up by reposting right-wing images of Democrats like Barack Obama, Kamala Harris, and Hillary Clinton making out-of-context motions with their hands that could scarcely be described as similar to his.

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Andrea Stroppa, a right-wing Italian friend and supporter of Musk, took the discussion in a whole different direction on Monday when she posted on X that Musk’s salute had Italian origins: "Roman Empire is back starting from Roman salute.”

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Some of Musk’s fans and followers on X hopped on the Roman bandwagon, claiming it absolved the titan of hate-mongering since it was less Hitler and more Nero.

The Roman salute's origins

The problem with claiming Musk was simply showing an appreciation for chariots and gladiators is there is no proof of the gesture being used in ancient Rome, according to historian Martin M. Winkler, who wrote a book about the salute. There is no Roman art, writing, or coins that display the gesture, according to Winkler. "The gesture of the raised right arm or hand in Roman and other ancient cultures that is attested in surviving art and literature had a significantly different function and is never identical with the modern straight-arm salute," Winkler wrote in his book, The Roman Salute.

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Instead, the hand motion like that used by Musk was popularized in 19th-century books, toga plays and, later, early 20th-century films as a fictional fixture of ancient Rome, the Guardianreports. Through those media depictions, the so-called Roman salute then became a favorite of 20th-century Hitler ally/Italian fascist Benito Mussolini and his political party. "...the salute as a unifier — and as a path to punish those who don't conform by immediately raising their arms — was present before Hitler came to power," according to Forward.

Upon gaining power in the late 1920s, Hitler and his cronies adopted the Italian gesture for themselves, according to to the BBC, and it symbolized fealty to the leader and his racist, anti-Semitic, xenophobic principles. Once World War II began in 1939 following Germany's invasion of Poland, pro-Hitler gestures and pronouncements had penetrated daily life. "In public, ordinary Germans were expected to praise Hitler and give the so-called German greeting ("Heil Hitler!")," according to the Holocaust Encyclopedia, which is hosted by the U.S. Holocaust Museum.

The Roman salute is conditionally allowed in Italy and outright banned in Germany. German chancellor Olaf Scholz responded to Musk's gesture by saying, "We have the freedom of speech in Europe and in Germany," he said, "what we do not accept is if this is supporting extreme right positions."