Numidia developed substantially under Masinissa, whose political authority was accompanied by a marked expansion of cereal cultivation. Ancient writers credited him with converting nomads into farmers, a formulation that overstates the transformation, since stock-rearing remained predominant. Nevertheless, agricultural production increased enough to generate surpluses for export, creating an economic foundation for later Roman expansion in the region.

Masinissa’s capital grew into a genuine city, although the population later attributed to it was probably exaggerated. Its urban culture was strongly Carthaginian: archaeological evidence includes more Punic stelae there than at any African site except Carthage itself. The language of Carthage also became increasingly widespread in Numidia and Mauretania, demonstrating the continuing influence of Punic urban culture beyond Carthaginian political control.

Numidia expanded while Rome increasingly favored Masinissa against Carthage. From the later second century BCE, Roman policy became more ruthless, and Masinissa added territories around the Gulf of Gabes and much of the Bagradas Valley. After Carthage was destroyed in 146 BCE, Rome recognized client kingdoms across much of North Africa, allowing Numidia to continue developing while remaining subject to royal rivalries, tribal autonomy, and Roman interference.

After Masinissa died in 148 BCE, Micipsa ruled until 118 BCE, during a period when commerce between Numidia, Rome, and Italy increased and Italian traders were present at Cirta. Micipsa’s death produced a contested succession involving his brothers and Jugurtha, a grandson of Masinissa. Jugurtha sought sole power, captured Cirta, and killed Italian residents there, prompting Rome to declare war.

Jugurtha mounted formidable resistance and temporarily inflicted military humiliation on Rome. His defeat came through the intervention of Bocchus, ruler of Mauretania, who betrayed him to the Romans. Rome then installed Gauda, another member of Masinissa’s dynasty, followed by his son Hiempsal. Hiempsal ruled for decades, briefly endured exile, and was credited with writing a book about Africa in Punic.

In Numidia’s final years of independence, Hiempsal’s son Juba joined the Pompeian cause during the Roman civil wars. After Caesar’s victory at Thapsus, Juba committed suicide, and Rome established direct rule over Numidia. The kingdom’s history therefore illustrates both the resilience of indigenous dynastic institutions and the increasing ability of Rome to determine succession and territorial organization in the Maghrib.