Palladium (protective image)

A palladium or palladion is an image or other object of great antiquity on which the safety of a city or nation is said to depend. The word is a generalization from the name of the original Trojan Palladium, a wooden statue (xoanon) of Pallas Athena that Odysseus and Diomedes stole from the citadel of Troy and which was supposedly later taken to the future site of Rome by Aeneas, where it remained until perhaps transferred to Constantinople and lost sight of after the conversion of the Empire to Christianity.

In English, since around 1600, the word "palladium" has been used figuratively to mean anything believed to provide protection or safety, and in particular in Christian contexts a sacred relic or icon believed to have a protective role in military contexts for a whole city, people or nation. Such beliefs first become prominent in the Eastern church in the period after the reign of the Byzantine Emperor Justinian I, and later spread to the Western church. Palladia were processed around the walls of besieged cities and sometimes carried into battle. In this more offensive role they may also be referred to as "vexilla" (singular vexillum, Latin for "battle standard").

The original Palladion was part of the foundation myths of both Troy and Rome. It was a wooden image of Pallas (whom the Greeks identified with Athena and the Romans with Minerva) said to have fallen from heaven in answer to the prayer of Ilus, the founder of Troy. In the Trojan War the besieging Greeks discovered that they would be unable to take the city while it was protected by it, and so Odysseus and Diomedes stole it from the citadel of Troy before taking the city by the ruse of the Trojan Horse. According to a later set of myths it was then taken to Rome, where an actual image, unlikely to have been actually of Trojan origin, was kept in the Temple of Vesta in the Roman Forum for centuries, and regarded as one of the pignora imperii, sacred tokens or pledges of Roman rule (imperium). The Roman story is related in Virgil's Aeneid and other works.

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