Following his missionary success in Guatemala, Cáncer proposed a peaceful mission to Florida. The peninsula had already been ravaged by the expeditions of Pánfilo Narváez and Hernando de Soto and was regarded as very hostile to the Spanish, and Cáncer argued that further violence would never bring about its conversion to Catholicism and submission. In 1547, King Charles V approved Cáncer's Florida mission. However, the royal decree stipulated that the mission land at Florida's upper east coast, avoiding hostile territory in southern Florida and the Gulf Coast where earlier conquistadors had gone.