The Esselen are too often regarded as the first California Native American tribe to become culturally extinct, much to the frustration of current generations of Esselen people. By about 1822, much of the California Indian population in proximity to the missions had been forced into the Spanish mission system. Due to the proximity of the Esselen people to three of the Spanish missions, Mission San Carlos in Carmel, Mission Nuestra Señora de la Soledad in Soledad, and Mission San Antonio de Padua in Jolon, the tribe was heavily impacted by their presence. The native population was decimated by disease, including measles, smallpox, and syphilis, which wiped out 90 percent of the native population, and by conscript labor, poor food, and forced assimilation. Most of the Esselen people's villages within the current Los Padres National Forest were left largely uninhabited. Professor Sherburne Cook, an expert in Native American populations, described the causes of the population decline: