At the time when Cæsar held the command in Gaul these same Dalmatians and other Illyrians, who were then in a very prosperous condition, took the city of Promona
from the Liburni, another Illyrian tribe. The latter put
themselves in the hands of the Romans and appealed to Cæsar, who was near by. Cæsar sent word to those who were holding Promona that they should give it up to the Liburni, and when they refused, he sent against them a strong detachment of his army who were totally destroyed by the Illyrians. Nor did Cæsar renew the attempt, for he had no leisure then, on account of the civil strife with Pompey. When the civil strife burst forth in war Cæsar crossed the Adriatic from Brundusium in the winter, with what forces he had, and opened his campaign against Pompey in Macedonia. Antony brought another army to Cæsar's aid in Macedonia, he also crossing the Adriatic in mid-winter. Gabinius led fifteen cohorts of foot and 3000 horse for him by way of Illyria, passing around the Adriatic.
The Illyrians, fearing punishment for what they had done
to Cæsar not long before, and thinking that his victory would be their destruction, attacked and slew the whole army under Gabinius, except Gabinius himself and a few who escaped. Among the spoils captured was a large amount of money and war material.