Which Franciscan priest set up a series of missions along the California coast?

Junípero Serra is renowned for establishing a network of missions along the California coast during the Spanish colonial period. He founded the first mission, Mission San Diego de Alcalá, in 1769, and subsequently established several others, such as Mission San Francisco de Asís and Mission Santa Clara de Asís. Serra's work was crucial in spreading Christianity among the indigenous populations and played a significant role in the cultural and economic development of California.

His efforts were part of a broader Spanish mission system aimed at colonizing and converting Native Americans, as well as facilitating Spanish claims to territory in California. This mission system significantly impacted the state's history, influencing California's demographics, culture, and architecture that can still be seen today.

The other individuals mentioned were involved in different capacities: Mariano Vallejo was a military leader and later a politician during the transition to statehood; Gaspar de Portolá was a military governor who led expeditions in California; and Jedediah Smith was an early American explorer and fur trapper. While each played important roles in California's history, it was Serra specifically who focused on establishing the missions that formed the backbone of the Spanish mission effort in the region.