After the great Byzantine victory at the
Battle of Ad Decimum, Belisarius and his army captured Carthage. Vandal king Gelimer set up at
Bulla Regia in
Numidia, about to the west of Carthage (at what is now the western border of modern
Tunisia). He knew that in his current state he would not be able to face Belisarius's forces, so he sent messengers to his brother Tzazon who was then campaigning in
Sardinia. When he received the message, Tzazon set about returning to Africa to join Gelimer. Meanwhile, Gelimer also attempted to divide the forces helping Belisarius. He offered rewards to the local
Punic and
Berber tribes for every Byzantine head they could bring, and sent agents to Carthage to attempt to have the Byzantine
Hun mercenaries—vital to his success at Ad Decimum—betray him. Tzazon and his army joined Gelimer early in December, at which point Gelimer felt his forces were strong enough to take the offensive. With the two brothers at the head of the army, the Vandal force paused on the way to Carthage to destroy the great
aqueduct which supplied the city with most of its water. Belisarius had fortified the city in the twelve weeks since Ad Decimum, but knew about Gelimer's agents and could no longer trust the Huns in his forces. Instead of waiting for a possible treachery during a siege, he formed up his army and marched out with the
cavalry at the front, the Byzantines in the center, and the Huns at the rear of the column. ==Battle==