Ancile in Wikipedia

The Ancile, in ancient Rome, is the legendary buckler shield of the god Mars, said to have fallen from heaven, upon Numa Pompilius. At the same time, a voice was heard which declared that Rome should be mistress of the world while the shield was preserved. The Ancile was, as it were, the palladium of Rome. Different authors give different etymologies of this word. Some derive it from the Greek ἀγκύλος, "crooked". Varro derives it ab Ancisu, as being cut or arched on the two sides, like the bucklers of the Thracians, called peltæ. Plutarch thinks the word may be derived from the Greek ἀγκών, "elbow", this weapon being worn on the elbow. The opinion of Varro, however, is more probable.[citation needed] Though there was but one Ancile that fell from heaven, there were twelve preserved, called the Ancilia; Numa, by the advice, as it is said, of the nymph Egeria, ordered eleven others, perfectly like the first, to be made. This was so that if anyone should attempt to steal it, as Ulysses did the Palladium, they might not be able to distinguish the true Ancile from the false ones. These Ancilia were preserved in the temple of Mars, and were committed to the care of twelve priests of Salii, instituted for that purpose by Numa [1]. They were carried every year, in the month of March, in procession around Rome, and on the 30th day of that month, were again deposited in their place. - Wikipedia

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