Twenty-one colonial-era missions traversed California stretching northward from San Diego to just beyond San Francisco. Founded by Franciscan missionaries beginning in 1769, these missions—along with four presidios (forts) and three pueblos (towns)—were central to Spain’s attempt to incorporate the Pacific Coast of northern New Spain into its enormous transatlantic colonial empire. Established in the late 18th century, just as Spain was secularizing missions elsewhere in New Spain, the California missions were cultural and institutional throwbacks and controversial from their inception. They prompted consistent and occasionally violent resistance from Native Californians. Furthermore, Europeans who visited Spanish California saw them as repressive colonial institutions. Indeed, during their sixty years of existence, the missions proved most adept at damaging the culture and shortening the lives of California’s Native Americans, the very people missionaries thought they would save by bringing them into the Catholic faith. By the time that Mexican government officials secularized the missions in the 1830s and parceled their lands and resources out to Mexican settlers, associates of the Mexican ruling elite, and a small number of Natives, California missions had shown themselves to be transformative and lethal agents of change. In the 21st century, their legacies are increasingly seen as negative, forever linked to the indefatigable and uncompromising missionary Junípero Serra, who was controversially canonized by Pope Francis in 2015.