Spanish colonization commenced on June 15, 1668 with the arrival of a mission led by Diego Luis de San Vitores, who established the first Catholic church. The islands were part of the Spanish East Indies, and in turn part of the Viceroyalty of New Spain, based in Mexico City. The Spanish-Chamorro Wars on Guam began in 1670 over growing tensions with the Jesuit mission, with the last large-scale uprising in 1683. Intermittent warfare, plus the typhoons of 1671 and 1693, and in particular the smallpox epidemic of 1688, reduced the CHamoru population from 50,000 to 10,000, finally to less than 5,000.