This article analyzes the meanings and uses of crosses in the interactions among diverse indigenous groups and colonizers in the Sonoran frontier of northern New Spain during the eighteenth century and beyond. By showing that colonial expansion was a process that included persuasion within a context of violence, it highlights diplomacy through exchanges facilitated by cultural parallels and hybridity between Christian and precontact Amerindian symbols and rituals. This approach illustrates that the sign of the cross became a widespread mechanism for initiating peaceful interactions. The emphasis on the hybrid use of crosses provides insight into the fluid interactions among Natives and colonizers through the adoption of this symbol and the role these Native groups had in implanting colonial culture in their societies. Ultimately, it shows the indigenous peoples’ reactions and strategies under colonial presence.