Contra Costa County, California
In 1821 Mexico gained independence from Spain. While little changed in ranchero life, the Mexican War of Independence resulted in the secularization of the missions with the re-distribution of their lands, and a new system of land grants under the Mexican Federal Law of 1824. Mission lands extended throughout the Bay Area, including portions of Contra Costa County. Between 1836 and 1846, during the era when California was a province of independent Mexico, the following 15 land grants were made in Contra Costa County.
The Mexican Frontier, 1821–1846
The Mexican Frontier, 1821–1846: The American Southwest Under Mexico by historian David J. Weber is a history of the part of Mexico's north and northwest that became part of the United States after the Mexican–American War. The book examines territories on the northern frontier of Mexico, including what is now Arizona, California, New Mexico, and Texas, in the twenty-five years after Mexico gained its independence from Spain. Weber emphasizes the role of Mexicans in the region through this period of transition, particularly before and during the Texas war of independence, as well as exploring the region as a whole while acknowledging its distinct communities.