SEGU´SIO
SEGU´SIO (Σεγούσιον: Eth. Σεγουσιανός, Eth. Segusinus: Susa), a city of Gallia Transpadana, situated at the foot of the Cottian Alps, in the valley of the Duria (Dora Riparia), at the distance of 35 miles from Augusta Taurinorum (Turin). It was the capital of the Gaulish king or chieftain Cottius, from whom the Alpes Cottiae derived their name, and who became, in the reign of Augustus, a tributary or dependent ally of the Roman Empire. Hence, when the other Alpine tribes were reduced to subjection by Augustus, Cottius retained the government of his territories, with the title of Praefectus, and was able to transmit them to his son, M. Julius Cottius, upon whom the emperor Claudius even conferred the title of king. It was not till after the death of the younger Cottius, in the reign of Nero, that this district was incorporated into the Roman Empire, and Segusio became a Roman municipal town. (Strab. iv. pp. 179, 204; Plin. Nat. 3.20. s. 24; Amm. Marc. 15.10.)It was probably from an early period the chief town in this part of the Alps and the capital of the surrounding district. It is situated just at the junction of the route leading from the Mont Genèvre down the valley of the Dora with that which crosses the Mont Cenis; both these passages were among the natural passes of the Alps, and were doubtless in use from a very early period, though the latter seems to have been unaccountably neglected by the Romans. The road also that was in most frequent use in the latter ages of the Republic and the early days of the Empire to arrive at the pass of the Cottian Alps or Mont Genèvre, was not that by Segusio up the valley of the Duria, but one which ascended the valley of Fenestrelles to Ocelum (Uxeau), and from thence crossed the Col de Sestrières to Scingomagus (at or near Cesanne), at the foot of the actual pass of the Genèvre. This was the route taken by Caesar in B.C. 58, and appears to have still been the one most usual in the days of Strabo (Caes. Gal. 1.10; Strab. iv. p.179); but at a later period the road by Segusio seems to have come into general use, and is that given in the Itineraries. (Itin. Ant. pp. 341, [p. 2.952]357.) Of Segusio as a municipal town we hear little; but it is mentioned as such both by Pliny and Ptolemy, and its continued existence is proved by inscriptions as well as the Itineraries; and we learn that it continued to be a considerable town, and a military post of importance, as commanding the passes of the Alps, until long after the fall of the Western Empire. (Plin. Nat. 3.17. s. 21; Ptol. 3.1.40; Gruter, Inscr. p. 111. 1; Orell. Inscr. 1690, 3803; Amm. Marc. 15.10; Itin. Hier. p. 556; P. Diac. Hist. Lang. 3.8; Greg. Tur. 4.39.)
Ammianus tells us that the tomb of Cottius was still visible at Segusio in his time, and was the object of much honour and veneration among the inhabitants (Amm. l.c.). A triumphal arch erected by him in honour of Augustus is still extant at Susa; it enumerates the names of the “Civitates” which were subject to his rule, and which were fourteen in number, though Pliny speaks of the “Cottianae civitates xii.” (Plin. Nat. 3.20. s. 24; Orell. Inscr. 626.) All these are, however, mere obscure mountain tribes, and the names of most of them entirely unknown. His dominions extended, according to Strabo, across the mountains as far as Ebrodunum in the land of the Caturiges (Strab. iv. p.179); and this is confirmed by the inscription which enumerates the Caturiges and Medulli among the tribes subject to his authority. These are probably the two omitted by Pliny. Ocelum, in the valley of the Clusone, was comprised in the territory of Cottius, while its limit towards the Taurini was marked by the station Ad Fines, placed by the Itineraries on the road to Augusta Taurinorum. But the distances given in the Itineraries are incorrect, and at variance with one another. Ad Fines may probably be placed at or near Avigliana, 15 miles from Turin, and 20 from Susa. The mountain tribes called by Pliny the “Cottianae civitates,” when united with the Roman government, at first received only the Latin franchise (Plin. l.c.); but as Segusio became a Roman municipium, it must have received the full franchise.
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