They are mentioned as AmbisontesbyPliny (1st c. AD),[1] and as Ambēsóntioi (Ἀμβησόντιοι) by Ptolemy (2nd c. AD).[2]
The GaulishethnonymAmbisontes means 'the people from around the Isontia', stemming from the root *amb(i)- ('around, on both sides') attached to the name of the river Isontia (modern Salzach).[3][4] The hydronym itself, while not necessarily Celtic, is most likely of Indo-European origin, and can be derived from the stem *[h₁]ish₁-ont- ('she who moves quickly').[5]
The Ambisontes lived in the upper valley of the Salzach river. Their territory was situated north of the Saevates and Laianci, south of the Alauni, and east of the Breuni and Cosuanetes.[6]
They are mentioned by Pliny the Elder as one of the Alpine tribes conquered by Rome in 16–15 BC, and whose name was engraved on the Tropaeum Alpium.[1]
de Bernardo Stempel, Patrizia (2015). "Zu den keltisch benannten Stämmen im Umfeld des oberen Donauraums". In Lohner-Urban, Ute; Scherrer, Peter (eds.). Der obere Donauraum 50 v. bis 50 n. Chr. Frank & Timme. ISBN978-3-7329-0143-2.
Delamarre, Xavier (2003). Dictionnaire de la langue gauloise: Une approche linguistique du vieux-celtique continental. Errance. ISBN9782877723695.
Falileyev, Alexander (2010). Dictionary of Continental Celtic Place-names: A Celtic Companion to the Barrington Atlas of the Greek and Roman World. CMCS. ISBN978-0955718236.