Gannicus was a Celtic slave, who together with the Thracian Spartacus, Crixus, Castus and Oenomaus, became one of the leaders of rebel slaves during the Third Servile War . In the winter of 71 BC, Gannicus, along with Castus, broke off from Spartacus, taking a large number of Celts and Germans with them, marking the second detachment of the rebellion. Gannicus and Castus met their end at the Battle of Cantenna in Lucania near Mount Soprano , where Marcus Licinius Crassus, Lucius Pomptinus and Quintus Marcius Rufus entrenched their forces in battle and defeated them.