Born Miguel Jose Serra in 1713 on the Spanish island of Majorca, he took the name "Junipero" when he made his final religious vows as a Franciscan monk at Palma in 1731. In 1749 he joined a band a Franciscans bound for Mexico City, which brought him to the New World. Not until 1767, when the Franciscans replaced the banished Jesuits in lower California, did Serra come to the United States. Fr. Serra founded his first mission on July 16, 1769, at San Diego.

Over the next 13 years, he was responsible for eight more in upper California, and 21 in total. All were connected by El Camino Real, the Spanish Royal Road. Appointed presidente of the California Franciscans, he traveled on foot from mission to mission, overseeing their progress and offering advice. His inspiration and spirit are considered vital factors in the successful Spanish occupation of early California.