The Battle of the Bagradas River was fought between a Carthaginian army led by Hamilcar Barca and a rebel force led by Spendius in 240 BC in what is now north-east Tunisia. Carthage was fighting a coalition of mutinous soldiers and rebellious African cities in the Mercenary War, which had started late the previous year in the wake of the First Punic War. The rebels were blockading Carthage and besieging the northern ports of Utica and Hippo (modern Bizerte). A Carthaginian army commanded by Hanno had attempted and failed to relieve Utica early in 240 BC. A second army was assembled in Carthage and entrusted to Hamilcar, who had commanded Carthaginian forces on Sicily for the last six years of the First Punic War.
The new Carthaginian army left Carthage and evaded the rebel blockade by crossing the Bagradas River (the modern Medjerda River) at its mouth. Rebel armies commanded by Spendius from both the Utica siege and a camp guarding the only bridge over the lower Bagradas River marched towards the Carthaginians. When they came into sight Hamilcar ordered the Carthaginians to feign a retreat. The rebels broke ranks to chase after the Carthaginians and this impetuous pursuit caused them to fall into confusion. Once the rebels had drawn close, the Carthaginians turned and charged them. The rebels broke and were routed. The Carthaginians pursued, killing or capturing many of the rebels and taking the fortifications guarding the bridge.
This victory gave Hamilcar freedom to manoeuvre and the operational initiative. He confronted towns and cities that had gone over to the rebels, bringing them back to Carthaginian allegiance. Spendius confronted Hamilcar again in the mountains of north west Tunisia and Hamilcar was again victorious. Spendius had his Carthaginian prisoners tortured to death. Hamilcar in turn had existing and future prisoners trampled to death by elephants. After two further years of increasingly bitter warfare the rebels were worn down and eventually defeated at the Battle of Leptis Parva.
Background
The First Punic War was fought between Carthage and Rome, the two main powers of the western Mediterranean in the 3rd century BC, and lasted for 23 years, from 264 to 241 BC. The two powers struggled for supremacy primarily on the Mediterranean island of Sicily and its surrounding waters, and also in North Africa. While the war with Rome was being fought on Sicily, the Carthaginian general Hanno led a series of campaigns that greatly increased the area of Africa controlled by Carthage. He extended its control to Theveste (modern Tébessa, Algeria) south-west of their capital and was rigorous in squeezing taxes out of the newly conquered territory to pay for both the war with Rome and his own campaigns. Half of all agricultural output was taken as war tax, and the tribute due from all towns and cities was doubled. These exactions were harshly enforced, causing extreme hardship in many areas.
After immense material and human losses on both sides during the First Punic War, the Carthaginians were defeated. The Carthaginian Senate ordered the commander of its forces on Sicily, Hamilcar Barca, to negotiate a peace treaty on whatever terms he could. Convinced that the surrender was unnecessary Hamilcar left Sicily in a rage and delegated negotiations to his deputy Gisco. The Treaty of Lutatius was agreed and brought the First Punic War to an end.
Mutiny
The post-war evacuation of the Carthaginian army of 20,000 men from Sicily was left in the hands of Gisco. He split the army into small detachments based on their regions of origin and sent these back to Carthage one at a time. He anticipated they would be promptly paid the several years back pay they were owed and hurried on their way home. The Carthaginian authorities decided instead to wait until all of the troops had arrived and then attempt to negotiate a settlement at a lower rate. They despatched the returning troops to Sicca Veneria (modern El Kef), away.