Julius Civilis, also known as Gaius or Claudius, was the son of a noble Batavian family; he was born about AD 25.
Like many Batavians, he joined the Roman army when he was a young man. He became the commanding officer of a cohort (battalion) in the German auxiliaries and acquired Roman citizenship.

Following an uprising against Nero in AD 68, he and his brother Claudius Paulus were accused of treason.Claudius Paulus was executed and Civilis was sent to Rome for trial. These events brought bitterness to his heart and he made a vow he would revanche his brother's death.
The death of Nero saved Civilis's life. He was acquitted by Galba, Nero's successor as the emperor of Rome, and returned to Germania. Prior to the uprising, Civilis had been the commander of a replacement cohort in the Batavian homeland.

After his first military action against the Romans, Civilis, according to an ancient custom, swore an oath to dye his hair red and let it grow until such time as he had annihilated the legions. This, together with the fact that he had only one eye, must have given him a striking appearance.