The Catholic presence in present-day Orange County dates to the 1776 establishment of Mission San Juan Capistrano, a Spanish mission founded by Father Junipero Serra and the Franciscan order. At the time the region was part of the "Las Californias" province of New Spain. In 1804 present-day Orange County became part of Alta California when "Las Californias" was split in two; Alta California then became part of Mexico when the latter gained independence from Spain in 1821. From the mission the missionary priests set out to convert the native population to Catholicism; over 4,000 people were converted between 1776 and 1847.