During the Roman civil war of 49–45 , Masinissa II and his cousin Juba I, ruler of the larger and more powerful kingdom of eastern Numidia, sided with the Roman general Gnaeus Pompeius against Julius Caesar. In 46 , Caesar and his allies defeated Masinissa and Juba, who committed suicide, at the Battle of Thapsus. Arabio managed to escape and join Pompeius' supporters in Hispania. The kingdom of his father was broken up and given to Caesar's allies: the western part to King Bocchus II of Mauretania and the eastern part, including Cirta, to Publius Sittius, a Roman mercenary captain, to be ruled as an autonomous principality. It is possible that Cirta had belonged not to his father's kingdom but to that of Juba.