In pre-Roman Gaul the Belgic tribe of the Veliocasses or Velocasses controlled a large area in the lower Seine valley, which retains a trace of their name, as the Vexin, in 52 they raised 3000 men to support which son of Celtillus the Avernian, leader of the Gallic tribes?
Veliocasses:  In 52 they raised 3000 men to support Vercingetorix, and fought alongside the Bellovaci in the final rebellion against Roman hegemony.
i don't know