This chapter deals with Italy in the period from the beginning of the Greek colonization through 133 BC. It focuses on the Italian peninsula, touching only briefly on northern Italy and the islands, or the world of non-Roman indigenous cultures. For addressing the question of the rise of Rome to the most powerful polity in Italy and a leading Mediterranean power, the chapter examines the impact of wars, treaties, and the founding of colonies, Greek as well as Etruscan and Roman, reciprocal influences, forced or spontaneous transformations. It distinguishes three major periods: from the earliest Greek contacts with Italy to the middle of the fourth century BC; from the middle of the fourth century, which saw Rome's military and political ascent and its rise to economic power, to the Second Punic War; and finally, from the Second Punic War, which caused profound upheavals in the Roman economy, to the period of the Gracchi.

The Senate took advantage of Carthage's difficulties in the Mercenary War to seize Sardinia. Polybius rightly regarded the latter action as unjustified and the subsequent Carthaginian resentment as a major cause of the Second Punic War. The treaty between Hannibal and Philip V of Macedon clearly envisaged Rome's continuing existence after a Carthaginian victory. Hannibal left Carthago Nova sometime in May, and reached the Rhone in September. Scipio, with an army destined for Spain, arrived by sea at the mouth of the Rhone at the same time. Scipio now sent the major part of his forces to Spain under the command of his brother Gnaeus, while he himself returned to Italy. Sicily and Sardinia were the prizes won by Rome as a result of the First Punic War and its aftermath. They were finally organized as provinces in 227 but in Sicily the kingdom of Syracuse, like the city of Messana, remained an independent state, bound to Rome by treaty.

The constitutional arrangements with which Rome emerged from the Second Punic War differed scarcely at all in form from those with which she had embarked upon that great struggle. Their essence remained the threefold structure of magistrates, Senate, and assemblies of the citizen body, the structure which the Greek observer Polybius was shortly to characterize as a 'mixed' constitution. Polybius saw that in the Roman governmental system the role of the Senate was central, that his aristocratic element predominated. This chapter examines the nature of Roman politics in the period. The idea that a major source of political power was a network of social connections which tended to be passed from one generation of a powerful family to the next prompted a further influential hypothesis. The combination of oligarchic predominance and popular electoral institutions had a further consequence which tended both to reinforce the pattern as a whole and to create ample scope for political competition conceived in personal terms.