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 First Mexican Republic, known also as the First Federal Republic (), was a federated republic and nation-state officially designated the United Mexican States (, ). "Independence transformed Mexico from Spain's largest and most prosperous colony to a sovereign nation suffering economic decline and political strife." The First Mexican Republic lasted from 1824 to 1835, when conservatives under Antonio López de Santa Anna transformed it into a centralized state, the Centralist Republic of Mexico.