Aegus and Roscillus were two chiefs of the Allobroges

Allobroges

The Allobroges were a Celtic tribe of ancient Gaul, located between the Rhône River and the Lake of Geneva in what later became Savoy, Dauphiné, and Vivarais. Their cities were in the areas of modern-day Annecy, Chambéry and Grenoble, the modern of Isère, and modern Switzerland...

, who had served Julius Caesar

Julius Caesar

Gaius Julius Caesar was a Roman general and statesman and a distinguished writer of Latin prose. He played a critical role in the gradual transformation of the Roman Republic into the Roman Empire....

 with great fidelity in the Gallic Wars

Gallic Wars

The Gallic Wars were a series of military campaigns waged by the Roman proconsul Julius Caesar against several Gallic tribes. They lasted from 58 BC to 51 BC. The Gallic Wars culminated in the decisive Battle of Alesia in 52 BC, in which a complete Roman victory resulted in the expansion of the...

, and were treated by him with great distinction. They accompanied him in his campaigns against Pompey

Pompey

Gnaeus Pompeius Magnus, also known as Pompey or Pompey the Great , was a military and political leader of the late Roman Republic...

, but having been reproved by Caesar on account of depriving the cavalry of its pay and appropriating the booty to themselves, they deserted to Pompey in Greece. Aegus was afterwards killed in an engagement between the cavalry of Caesar and Pompey.