Mission San Antonio de Padua was built as the 3rd mission along the proposed Camino Real (Kings Road) between the San Diego Bay and the San Francisco Bay. Russia occupied the lands north of San Francisco. King Carlos of Spain (who occupied the lands of Mexico) used missions as a means of controlling the lands of what was then called Alta California. It was cheaper than using military powers. King Carlos used his military to control bays along the Pacific Ocean and sent a handful of soldiers to each mission to help control uprisings. Father-President Junipero Serra was sent from Mexico (from Baja CA) to establish a chain of missions, eventually plotted to be a day's ride (or 3 days walking) apart. But each mission also had to be profitable, requiring a stable water source and fertile lands in order to grow crops and livestock. Mission San Antonio also had a Native American population that was very friendly to the Catholic Church. It helped in the conversion of neophytes (converts).
The missions were built to help spread Christianity to the New World and to colonize the the land in Alta California. It was wilderness, and not attractive to settlers. The Native Americans were already here. They were brought to the missions, baptized, and became "civilized".
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