This chapter will explore Vittoria della Rovere’s religious identity and piety as expressed through her relic collecting practices. Relics by their very nature are mobile and they are also invested with emotional and spiritual meaning. In the early modern period they were exchanged and collected, gifted, sought after and inherited, and they were housed in urn-like sacred monstrances that facilitated their display and mobility. I will examine the relics that circulated in the Medici court by focusing on those the Grand Duchess herself collected, gifted or exchanged, the elaborate reliquaries she commissioned to house and display them and on the collections that she inherited from her mother-in-law Archduchess Maria Maddalena of Austria and from her brothers-in-law, Cardinals Leopoldo and Giovan Carlo de’ Medici. Vittoria della Rovere’s governance of holy relics thus expressed both a collective Medici faith, and her own deep spirituality, thereby legitimating her authority to govern the Tuscan people and state.