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.