This paper explores piety and ceremonial practices in medieval Split, with a focus on their role in the social and spiritual life of the city. Piety was not only an expression of personal spirituality but also a public act that shaped daily activities, rituals, and shared values. Split was deeply immersed in religious activities that encompassed politics, public ceremonies, and private rituals. The Church played a key role in shaping moral and ethical norms, acting as the supreme authority. Through charitable legacies, substitute pilgrimages, and participation in brotherhoods, believers not only expressed their devotion to faith but also established and maintained traditions. The paper focuses on the veneration of saints who had, and still have, an important role in the religious life of Split. These include the martyrs St. Staš, Arnir, and Felix, with a special emphasis on the city’s patron saint, St. Domnius. Additionally, it analyzes the role of the Virgin Mary, whose cult became highly significant during the transition from the medieval to the early modern period. The second, main part of the paper is dedicated to the ceremonial practices of the Feast of St. Domnius and the analysis of material sources such as charitable legacies, which examine how religious practices were formed in medieval Split, preserving and developing its cultural and religious identity. An analysis of the city’s statutes, compared to those of other Dalmatian cities, provides insight into the specific religious practices of the region, while the works of medieval chroniclers supplement our understanding of the historical context. The final part of the paper deals with the influence of socio-political factors on changes in the expression of piety.