The Second Punic War (218 - 201 BC) was a disaster for Rome. Hannibal's stratgy was bankrupt when Rome did not collapse after Cannae. Although he gained Carentum (212 BCE) he lost Cpea (211 BCE) and Carthage was defeated at a battle on the plain of Lamo (212 BCE). The outcome of the 2nd Punic War was a major turning point in ancient history of Western Civilization. It had profound effects on the political, economic and religious life of Italy, as well as the entire Mediterranean basin. For many generations, no power could endanger or threaten the existence of Rome. But Italy suffered horribly in the war. During the war many fields were burned and livestock and villages were decimated. The topsoil was lost leaving Italy permanently impoverished. Many other wars happened afterward, with Syria, Macedonia, Greece and Asia Minor and most of the Levant which got conquered by the Romans. In 133 BCE the King Attalus II of Pergamum (with Asia Minor just across the Bosporus gave his kingdom to th romans after his death). The benefits of peace spread across all its adversaries and now was rich and proud and powerful.
But its suscces oversears was not without severe social and political cost at home. Expansion created pressure groups within the Roman population, which evetually tore apart the very fa bric of the republic. A new class of the "equites" was created, much like the middle class since it was below the senatorial class. But in practice the equites were members of the upper class and many of them were memers of Senaotorial class or noble families. They contacted almost all of the commercial activity and they invested their overseaas.
During Hannibal's invsion, small farmers were forcd to desert their farms and migrate to cities for protection. After the war, equites and senators bought this land and formed it into large estates (latifundia) which they worked with gangs of slaves. NUmbers of slaves were imported from overseas as a result of Rome's imperialism (prisoners of war were the chief source of slavery int eh ancient world). Cheap slave labor naturally drives out more expensiv free labor, so Rome's success overseas exacerbated the plight of the small farmers and forced increasing numbers of them off their land and into the cities, especially Rome. These farmers, unemployed citizens, formed yet another class: the proleteratii.
During the 2nd Punic War the proleteratii began to increase while small farmers were driven off their land. Since they were the mainstay of the army and the backbone of the army, this caused an alarming and harmful change in Roman society. The small farmers formed the manpower pool from which the Roman army was drawn and they had made the Roman expansion possible. Without them, all the gains of imperalism would be lost. Yet this class which had borne the brunt of the fighting which made Rome great received none of the rewards. This situation of rapid social change and distorting economic desplacement among Italy's population put such a severe strain on the body politic of the Roman Republic that it was eventually ripped asunder.