- Strategic location: The mission was built on a hilltop overlooking the Pacific Ocean, which made it an ideal location for defense against attacks by Native Americans or other enemies. It also provided a clear view of the surrounding area, making it possible to spot approaching ships or other threats.
- Water resources: The mission's location near the Santa Barbara Channel provided a reliable source of fresh water for the friars and the Native American converts who lived at the mission. The mission also had access to a nearby creek that could be used for irrigation.
- Native American population: The area around Santa Barbara was home to a large population of Native Americans, including the Chumash people. The friars hoped to convert the Native Americans to Catholicism and to use the mission as a base for further missionary efforts in the region.
- Climate: The climate of Santa Barbara is mild and Mediterranean, with warm summers and mild winters. This climate was ideal for the cultivation of crops and livestock, which were essential for the mission's economy.