Veliocasses

They are mentioned as Veliocasses by Caesar (mid-1st c. BC) and Pliny (1st c. AD), as Ou̓éliokásioi (Οὐέλιοκάσιοι; var. οὐενελιοάσιοι) by Ptolemy (2nd c. AD), and as Velocasses by Orosius (early 5th c. AD).

The meaning of the Gaulish ethnonym is uncertain. The first part is certainly the Gaulish stem uelio-, which could either derive from Proto-Celtic *wēliyā- ('modesty'; cf. OIr. féle, OBret. guiled 'honestas'), or else from Proto-Celtic *wēlyo- ('better'; cf. Welsh gwell 'better'). The second etymology is semantically more probable for a tribal name, but the unknown length of the vowel e in uelio- makes it difficult to conclude with certainty.

The meaning of the second element -casses, attested in other Gaulish ethnonyms such as Bodiocasses, Durocasses, Sucasses, Tricasses, or Viducasses, has been debated. It has traditionally been interpreted as '(curly) hair, hairstyle' (cf. Old Irish chass 'curl'), perhaps referring to a particular warrior coiffure. On this reading Veliocasses has been rendered as 'the curly ones', or 'those with very curly hair'.

Other scholars have instead connected the element with metalworking. Patrizia de Bernardo Stempel interprets the -casses ethnonyms as helmet-names, glossing Veliocasses as 'those with the good (i.e. harder) helmets' and treating such names as evidence that the metalworking era had begun. Mélanie Mairecolas and Jean-Marie Pailler, who link cass- to 'tin' rather than to 'hair' (cf. Gaulish Cassi-dannos, 'magistrate in charge of bronze coins', Britt. Cassivellaunus, 'Chief-of-Tin'; also Greek κασσίτερος 'tin'), propose instead 'those with the better metal', 'better through the metal', or 'those with the metal of a chief'.

The county of Vexin, attested in 617 as pagus Veliocassinus ('pagus of the Veliocasses'; Vilcassinum in 1092, Vulesin in 1118), is named after the ancient tribe.

The territory of the Veliocasses lay between the Parisii, the Caletes, and the Bellovaci, primarily north of the lower course of the Sequana (Seine), and to a limited extent also south of the river. Wooded highlands formed a natural boundary with the Bellovaci, who held sway in that region. The Sequana also separated them from the Lexovii and the Aulerci Eburovices.

During the pre-Roman period, their capital was probably the oppidum of Camp de Calidou (near Caudebec), then Rotomagus (present-day Rouen) after the reign of Augustus (27 BC-14 AD). In the 2nd century AD, the settlement served as a significant harbor for exports bound for Britain.

In 57 BC, during the Gallic Wars, they supplied ten thousand men to the army of the coalition of Belgic peoples led by the Bellovaci, but in 52 BC they sent only three thousand men to the army of the Gallic coalition. They again took part the following year in the mobilization of the chiefs Correos and Commios.

As for the neighbouring Calates, whether the Veliocasses should be classified as Gallic or Belgic is debatable.