Maybe more relevant: https://en.wikipedia.org/wiki/Roman_salute

> Although it originated during the 18th century in France, it is pseudohistorically associated with ancient Rome.

> According to an apocryphal legend, the fascist gesture was based on a customary greeting which was claimed to have been used in ancient Rome. However, no Roman text describes such a gesture, and the Roman works of art that display salutational gestures bear little resemblance to the modern "Roman" salute. The salute had in fact originated more than a millennium later, in Jacques-Louis David's painting The Oath of the Horatii (1784)