The spread of Christianity in Italy, as elsewhere throughout the empire, was greatly aided by the imperial support it received from the time of the emperor Constantine's conversion. The conversion of Italy's elites is one significant marker of religious change; once the elite, in Rome especially, but also throughout Italy, had converted, the empire could be proclaimed Christian. This chapter focuses on three separate social elites in three different but important cities in Italy: the senatorial aristocracy in Rome; the municipal provincial elite in Aquileia; and the imperial bureaucratic upper class in Milan. The elite of each city adopted Christianity over the course of the fourth and fifth centuries, but the paths they took and the Christianity they embraced differed. The conversion of Italy's elites was a gradual process of change within which the encouragements of emperors and bishops were mediated by specific elite institutions, ideas and behaviours. This involved a gradual turning away of pagans from pagan institutions.