Dumnorix

Dumnorix (spelled Dubnoreix on coins) was a chieftain of the Aedui, a Celtic tribe in Gaul in the 1st century B.C. He was the younger brother of Divitiacus, the Aedui Druid and statesman. The Aedui were allies of Rome, but Dumnorix was a leader of the tribe’s anti-Roman faction, who “…thought it better to be dominated by their fellow Gauls… rather than the Romans.”

In the years preceding Julius Caesar’s governorship of Transalpine Gaul the Helvetii tribe planned a great migration from northeast Gaul to western Gaul. Orgetorix, a prominent Helvetii chieftain, conspired with Dumnorix, and Casticus of the Sequani to make themselves kings in their own tribes. Then by their combined power rule all of Gaul in a Gallic version of the triumvirate. To strengthen the alliance Orgetorix married his daughter to Dumnorix. However, the conspiracy was discovered and Orgetorix died a short time after amid rumors of suicide. Dumnorix used his influence to persuade the Sequani to allow the Helvetii to migrate through their territory.

Upon arriving in Gaul in 58 BC Caesar opposed the migration militarily. He built fortifications at Lake Geneva and either requested or demanded that the Aedui, who had been named friend and ally of Rome, supply his soldiers with grain. Dumnorix was very popular and had a large contingent of person retainers. He used his influence to delay the grain supply. Caesar forced the Helvetii to take an alternate path, then inflicted a devastating defeat on the tribe at the Battle of the Arar.

Caesar pursued the Helvetii, using the Gallic cavalry to screen his advance. Dumnorix’ personal retainers made up a sizable contingent of the Gallic auxiliary. Dumnorix colluded with the Helvetii and at a key moment in an engagement withdrew his unit, giving the Helvetii the victory.

With his grain supply desperate, Caesar summoned the leaders of his Gallic allies. Liscus, the chief magistrate or Vergobretus of the Aedui, revealed to Caesar that Dumnorix was responsible for withholding the supplies and had also been in command of the unit whose flight had cost him the cavalry engagement. Dumnorix was spared any serious retribution at the intervention of his brother Diviciacus, who had good relations with Caesar and the Romans. Caesar agreed instead to place Dumnorix under surveillance.

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