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.
First Mexican Republic
The republic was proclaimed on November 1, 1823 by the Constituent Congress, months after the fall of the Mexican Empire ruled emperor Agustin I, a former royalist military officer-turned-insurgent for independence. The federation was formally and legally established on October 4, 1824 when the Federal Constitution of the United Mexican States came into force.