Earliest literary evidence
The earliest record of a settlement at Ajaccio having a name ancestral to its name is the exhortation in Epistle 77 written in 601 CE of Gregory the great to the Defensor Boniface, one of two known rectors of the early Corsican church, not to leave Aleria and Adjacium without bishops. There is no earlier use of the term and Adjacium is not an attested Latin word, which probably means that it is a Latinization of a word in some other language. The Ravenna Cosmography of about 700 CE cites Agiation, which sometimes is taken as evidence of a prior Greek city, as -ion appears to be a Greek ending. But, there is no evidence whatever of a Greek presence on the west coast and the Ionians at Aleria on the east coast had been expelled by the Etruscans long before Roman domination. The origin of the name is a mystery but is believed to be aboriginal.
Ptolemy, who must come the closest to representing indigenous names, lists the Lochra River just south of a feature he calls the "sandy shore" on the southwest coast. If the shore is the Campo dell'Oro (gold because of the sand?) the Lochra would seem to be the combined mouth of the Gravona and Prunelli Rivers, neither one of which sounds like Lochra.
North of there is a Roman city, Ourchinion. His western coastline is so distorted, however, that it is impossible to say where Adjacium was; certainly, he would have known its name and location if he had had any first-hand knowledge of the island and if in fact it was there. Ptolemy's Ourchinion is further north than Ajaccio and does not have the same name. It could be Sogone. The lack of correspondence between Ptolemaic and historical names known to be ancient has no defense except in the case of the two Roman colonies, Aleria and Mariana. In any case the population of the region must belong to Ptolemy's Tarabeni or Titiani people, neither of which are ever heard about again.
Archaeological evidence
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