The tradition holds that the Palladium was a real heaven-sent image on which the fate of cities turned. Scholarship treats it as a cult legend: the motif of a city-protecting image is widespread in the Greek world, multiple cities asserted possession of the true one, and the Roman version binds the object to a foundation myth designed to link Rome to Troy. Because the image was hidden by definition and never examined or depicted from life, every source stands at one or more removes from any object. Its existence as a physical artifact cannot be established, which is why it is classed here as legendary, with the honest caveat that Rome did maintain and venerate something it called by this name.
Because the Palladium is attested only in literary sources and no candidate object has ever surfaced, its authenticity cannot be assessed by the material and scientific methods this atlas applies to later, physically surviving relics; there is nothing to radiocarbon-date or to examine under a microscope. What can be assessed is the ancient tradition's own internal inconsistency: Greek sources already disagreed about whether Troy's Palladium was ever actually removed to Rome at all, whether copies existed specifically to protect the true image from theft, echoing the later, unrelated legend of the Ancilia, and whether the Temple of Vesta's own image was itself already understood by Romans to be one such copy rather than the original.