Tustin is a city located in Orange County, California, in the Los Angeles metropolitan area. In 2019, Tustin had a population of 79,348. The city is located next to the county seat, Santa Ana, and does not include North Tustin.
Members of the Tongva and Juaneño/Luiseño nations long inhabited this area. After the 1769 expedition of Gaspar de Portolà, a Spanish expedition led by Father Junipero Serra named the area Vallejo de Santa Ana (Valley of Saint Anne). On November 1, 1776, Mission San Juan Capistrano became the area's first permanent European settlement in Alta California, New Spain.
In 1801, the Spanish Empire granted 62,500 acres (253 km2) to Jose Antonio Yorba, which he named Rancho San Antonio. Yorba's great rancho included the lands where the cities and communities of Olive, Orange, Villa Park, Santa Ana, Tustin, Costa Mesa and Newport Beach stand today. Smaller ranchos evolved from this large rancho including the Rancho Santiago de Santa Ana.
After the Mexican-American war, Alta California became part of the United States and American settlers arrived in this area.