Initiated in San Diego in 1769 by the Mallorcan missionary Junípero Serra, the California missions eventually numbered twenty-one and spanned coastal California from San Diego to the San Francisco Bay Area. Spanish officials viewed the missions as necessary anachronisms, founded as they were long after the Crown had closed down most missions in New Spain. But missions were useful to the Crown in California because missionaries were inexpensive and zealous in their devotion to turning indigenous frontier peoples into loyal Catholics and taxpaying citizens. Furthermore, they often came to settle regions that Spanish settlers had no interest in colonizing. Missionaries came to California with tried and true techniques of recruitment as well as military and biological allies in the form of germs, plants, and animals. Thus into the California missions, in small groups over decades, came tens of thousands of Native Americans, many driven into the Franciscans’ arms by European-introduced diseases that undermined village life and by environmental changes that accompanied Spanish colonization and undercut Native subsistence practices. In the missions, Indigenous labor and productivity became the backbone of the colonial region and a source of enduring controversy. Some baptized Natives would learn European trades and the rudiments of Catholicism and the Spanish language, but disease shortened the lives of most. From their early days the missions prompted Indigenous resistance and invited criticism from European visitors and Spanish bureaucrats who saw them as relics of a bygone era during which Native labor was controlled by padres. By the time the Mexican government secularized the missions in the 1830s and parceled out the missions’ lands and resources among well-connected colonists and a small number of Natives, the missions had proven themselves to be potent and deadly agents of change. Despite the heavy toll that they exacted on Native life and culture, the literature on the California missions—with a few notable exceptions—remained laudatory through the middle of the 20th century, written as it was by boosters and hagiographers. Since the 1980s, however, a growing body of work has documented the degree to which the missions upended Native lives and communities. Increasingly, and largely in response to the Catholic Church’s decades-long campaign to canonize Serra that culminated in 2015, this new work has examined in depth the ways in which Natives maintained their culture and survived the challenges of mission life and Spanish colonialism. The most recent studies of the missions combine insights from archaeology, anthropology, and history; a deep reading of documents in the archives of Mexico and across California; and a mining of the mission registers created by the Franciscans. The result is a vivid, harrowing, data-driven, polyvocal rendering of the California missions. This new work transcends both earlier triumphalist accounts depicting Franciscan missionaries as gentle and homogenous padres who brought the glories of European civilization to backwards peoples and censorious indictments of those padres as all-powerful colonists who destroyed all that was good in Native culture.