During the early Seventeenth Century the order of Our Lady of Mercy developed a new strategy to achieve the official recognition of its most important saints by the Vatican. This canonisation policy included the creation of an important body of hagiographic literature, along with paintings, sculptures and engravings that codified the image of Peter Nolasco, Raymond Nonnatus or Mary Cervellon, among others. The essay focuses on the specific case of Saint Serapion, the last Mercedarian saint to be canonized in !&(). Born in England, martyrized in Africa and promoted to sanctity by the Spanish Monarchy, Serapion combines different identities that will be analysed within their political and religious context. The aim of the research is to examine the Mercedarian sources, in order to understand the meaning of Saint Serapion's iconography.