Belisarius led armies from the Byzantine (or Eastern Roman) empire in the 6th century AD. He fought the Persians on the eastern front of the empire and eventually fought a long war to reclaim Italy from Gothic tribesmen. The subject of interest here is the Vandal war in North Africa. The Emperor Justinian, taking advantage of a revolt against Vandal rule and a peace with the Persians, sent Belisarius with a small force of ten thousand men to attack the formerly held territories of the Roman Empire in North Africa.
One the invasion landed on the beach; Belisarius marched towards the Vandal’s capital at Carthage. He ordered his soldiers to pay for their supplies and forbade them from pillaging. As a result, they had the support of the people and moved “as if in their own land.” Gelimer, the Vandal king, planned an ambush along their likely route. At Ad Decimum, Gelimer planned a three-pronged attack. His brother, Ammatas, would attack the advance of Belisarius from the front. Another force under Gibamundus would attack Belisarius from the left flank. And Gelimer would use his local knowledge of roads to take an interior route to attack Belisarius from the rear.
The plan compensated for the division of forces by relying on the surprise of attacking simultaneously form multiple directions. Unfortunately, the plan collapsed quickly. The cavalry of Belisarius defeated the flank attack led by Gibamundus and the latter fell among the fighting. A short time later the frontal attack led by Ammatas smashed into the Byzantine force. He engaged the vanguard of Belisarius’ army, but the former hadn’t prepared to attack Belisarius so far north; as a result, Ammatas had his army spaced out along the road. The forward units were defeated piecemeal as they marched into the Byzantines, and then as those units retreated, they affected the next column and forced them to retreat and so on. His entire force ended up fleeing in a panic back towards Carthage.
Finally, Gelimer arrived and attacked towards the north at what he thought was the rear, and already engaged, army of Belisarius. If the plan had worked, the two attacks by Gibamundus and Ammatus would mean that Gelimer attacked the rear for a coup de grace like Helamans “furious” attack upon the rear of the Lamanite army in Alma 56:52 with his Stripling Warriors. Gelimer routed the screening cavalry (the force that defeated Ammatas earlier), who then fled to the safety of the main camp of Belisarius. Gelimer regrouped his forces and stood poised to attack the bulk of the army of Belisarius. He hadn’t achieved his goal of attacking in the rear for the finishing blow, but still commanded motivated soldiers flushed with initial victory, while Belisarius, seemingly under attack from every direction, was trying to reorder his forces. Yet upon seeing the dead body of his brother Ammatus, Gelimer paused to assess the situation. The pause by Gelimer allowed Belisarius to rally his fleeing cavalry, and counterattack with his entire force. Gelimer fled south, and Belisarius had an open road to Carthage. He took the city, defeated the resurgent Gelimer and reclaimed North Africa for the Byzantine Empire.