Sagii
The Sagii were a Gallic tribe that lived in and around civitas Saiorum during the late Roman period. They succeeded the Esuvii mentioned in the 1st century BC by Caesar and Pliny.
Name
Stefan Zimmer has connected the ethnonym Sagii to the Gaulish verbal root sag-, yielding the interpretation 'skilled trackers'.The toponym Sées, attested as civitas Saiorum ca. 400 AD derives from the tribal name through a phonetic development from Sagii to ''Saii.''
Geography
Their chief town was civitas Saiorum, which was previously the chief town of the Esuvii.Another settlement, located at Fontaine-les-Bassets, was occupied from the early 1st to the 3rd century AD, with unknown causes for its abandonment. Together with Sées, it represents the largest urban complex known within the civitas of the Esuvii, and later that of the Sagii. Situated on the Roman road linking Bayeux and Vieux to Chartres and Évreux, it was the substantial staging site along this route in the region. The site may have functioned as a secondary settlement near the boundary between the Sagii and Lexovii, but it has also been suggested that it served as the chief town of the Esuvii, since the Sagii do not appear in ancient sources before the 3rd–4th centuries. The late attestation of the Sagii raises the possibility that two civitates existed in succession, or that they were later merged.