This article proposes to redefine the free Muslim in Ancien Régime Europe as a legal figure of poverty who benefited from rights that were reserved for their social integration. This arrangement was coveted by individuals who had no connection with Islam but who were in an equivalent situation of social uncertainty. Some trials of the Inquisition reveal itinerant Muslims in Spain during the 18th century who were suspected of having renewed their baptism a number of times. Among the accused were some individuals who turned out to be Old Christians (Spanish and Italian), who had dressed up as Muslims so that they could be baptized again. In light of these cases, this article examines the meaning of baptism for Muslims, not as a process of cultural assimilation in Catholic societies but as a process of social affiliation to a local community. By making conversion available to itinerant Muslims, the community accepted their tutelage. It recognized them as belonging to Islam and, as such, looked on them in the same way they would have looked on abandoned minors. The conversion process appears therefore to have been a specific welfare system, which aimed to establish a stable affiliation within a household that was contingent upon a dependent relationship with the godfather. This relationship manifested in various ways, with dependencies ranging from servitude to adoption.