The battle following the defection of Numidian chieftain Naravas to Hamilcar Barca was fought between Carthaginian forces commanded by Hamilcar Barca and part of the combined forces of Carthage's former mercenary armies during the Mercenary War, which Carthage had formerly employed during the First Punic War, and those of rebelling Libyan cities supporting the mercenaries.
A rebel army under the command of Spendius, which included a contingent of Gauls under Autharitus and a group of Numidians under Naravas, shadowed Hamilcar’s army. Spendius managed to trap the Carthaginians in a valley mountain after some time. The defection of Naravas allowed Hamilcar to escape the trap. Spendius then chose to engage the Carthaginian army, and in a hard fought battle Hamilcar emerged victorious.
The First Punic War ended with the Roman victory in the Battle of Aegates Islands in March 241 BC and Carthage authorizing Hamilcar Barca to start peace negotiations with Rome. The eventual settlement between Rome and Carthage included evacuation of Sicily by Carthage and payment of 3,200 silver talents to Rome as war reparations, 1,000 (21 tons of silver) immediately and 2,200 (56 ton of silver) in ten yearly installments. After paying Rome the indemnity which was part of the treaty, it could not easily pay the army of some 20,000 mercenaries it had employed to fight against Rome.
Delays in dealing with the mercenaries eventually led to the gathering of the entire army and their families in Sicca Veneria (modern El Kef), where they demanded payment from the Carthaginian negotiator Hanno the Great. The exact amount owed the mercenaries can only be guessed, but given the back pay, ration money and any other rewards promised, it probably was a substantial amount, which the mercenaries inflated after they reached Sicca. When Hanno refused their demands, as Carthage actually hoped to reduce the payment amount, and mercenaries were unsympathetic about the financial difficulties of Carthage, the negotiations broke down and the mercenaries seized Tunis. Carthage then sent provisions to Tunis and agreed to all the demands of the mercenaries, and sent Gisco to pay off the demanded amount.
Gisco began to pay off the mercenaries nationality by nationality, and events may have ended there, but two mercenary leaders, Spendius and Mathos, fomented revolt among the Libyan troops, for their own personal reasons, and were able eventually to persuade the entire mercenary army to revolt. The mercenaries seized the Carthaginian negotiators and the money. Matho used the funds to pay off the amount due to the mercenaries and fund the war effort. After settling the payments of the mercenaries, the rebels called upon the Libyan towns and cities under Carthaginian control to join the revolt. Several Libyan cities joined the revolt, providing men and funds (Libyan women donated personal possessions and jewels) to gather a force of 70,000. These events probably took place in the autumn/winter of 241 BC.
After the defeat of Spendius at the Battle of the Bagradas River by Hamilcar Barca in 239 BC, the rebel survivors scattered to Utica and Tunes, while Hamilcar captured the rebel camp by the river then cleared the area outside Utica of rebel forces. Hamilcar chose not to join forces with Hanno the Great and measure swords with Matho, whose army was blockading Hippo Acra. Hamilcar instead launched a campaign to subdue towns along the River Bagrades, some by force and some through negotiations. By doing so Hamilcar was reducing the rebel’s ability to draw recruits and supplies and securing for Carthage the same resources. It is not know if Hamilcar garrisoned any towns of any specifics regarding the terms offered to them. In response to Hamilcar’s activities, Spendius marshaled another army at Tunes, which included a Gallic contingent under Autharitus, and Numidians including a 2,000 strong cavalry detachment under Navaras, and moved out to confront Hamilcar. It is not known if Hamilcar had been reinforced by Carthage or he had incorporated the rebel prisoners into his army.
While Carthage’s armies were busy fighting rebels inland, the Carthaginian navy was patrolling the African coast. They happened to capture several Roman and Italian merchant ships running supplies to the rebels in 240 BC. The rebels had no fleet to counter these activities.
The army commanded by Spendius was probably larger than the Hamilcar’s army, although it had no elephants. Numidian cavalry gave Spendius a range of options. The Rebels army followed Hamilcar’ army, Spendius chose not to take the towns that had changed sides, but focused on keeping to the high ground, away from the cavalry and elephants of the Carthaginians, refused open combat and continually raided the Carthaginian soldiers. A war of attrition worked for the rebels with their superior numbers they could take more losses that the Carthaginians could. Spendius probably also awaited reinforcements and a favourable condition to engage Hamilcar’s army.
It is not known what measures Hamilcar employed to counter the harassment tactics of Spendius, or the exact path Hamilcar took since his victory over Spendius at Bagradas river. However, his army was on the move, helping to expand the sphere of Carthaginian control along the Bagradas river. In course of his march, Hamilcar entered a mountain valley and encamped against the advice of his staff. Spendius blocked the valley exit with his Libyan contingent, threatened the camp with his main body while the Numidians took position on the Carthaginian rear. Hamilcar’s army was trapped with no hope of relief. Cut off from provisions, Spendius only had to wait until hunger drove Hamilcar into desperate measures. The exact location of this mountain valley is not known, it is speculated to be either near the town of Nepehris, or at some location further to the south or southwest.
Navaras defects to Hamilcar
Navaras was a Numidian chieftain commanding 2,000 horsemen and guarding the path through which Hamilcar Barca’s army had entered the valley. He had family ties with Carthaginians and decided to switch sides. Navaras approached the Carthaginian camp undetected with a small escort, signaled for a parley and entered the camp unarmed and alone. He won Hamilcar’s trust and was promised the hand of Hamilcar’s daughter in exchange for his help. Navaras returned to his army, and deserted to the Carthaginians at the agreed upon time and before the rebel army could take action. Hamilcar exited the trap unopposed and regained his freedom of maneuver.
Soon after Hamilcar’s army escaped the trap and was joined by Navaras, Spendius gave up his harassing tactics and decided to give battle. It is not known what brought about this change in tactics, but Hamilcar engaged the rebels in battle. Little is known of the numbers involved or formations used, except that the battle was hotly contested and Carthaginians ultimately emerged victorious. Rebel losses were 10,000 killed and 4,000 captured. Spendius and Autaritus escaped the battle and made for Hippo. Carthaginian losses are not known.
Hamilcar decide to show clemency to the rebel prisoners. He offered to enlist those who were willing to serve under him, the others he offered to let go if they promised to leave Africa, and a substantial number joined the Carthaginian side. By doing this, Hamilcar could entice deserters away from the rebel army, a fact which the rebel leaders were keenly aware of. Hamilcar next began mopping up action of the surrounding countryside.
A series of events also took place while Hamilcar was campaigning and Hanno the Great was keeping watch on Matho’s army, the sequence of these events can only be speculated on. The Carthaginian mercenaries posted in Sardinia rebelled and began a massacre of Carthaginians. Carthaginian general Boaster and the surviving Carthaginians were besieged in citadel, exact location not known, and no prisoners were taken once the fort fell. Rebels then seized control of the Carthaginian areas, cutting off supplies, taxes and recruits from Carthage. Carthage, although heavily engaged against the rebels in Africa, began preparations to send an expedition to recover Sardinia. Rome sent an embassy to Carthage to demand the release of the Italian traders held by Carthage. Carthage freed the prisoners, which would bring unexpected dividends in the short run.