After Mexico won independence in 1821, California became part of the First Mexican Empire. The Mexican government was determined to secularize the missions, remove the natives and the ownership of the mission from the control of the Franciscan missionaries. This allowed foreigners to own land in the province once they had naturalized and converted to Catholicism. The most important thing is that the new Mexican republic was determined to move to secularize the missions, remove the natives and the ownership of the mission from the control of the Franciscan missionaries.
Under the terms of the treaty negotiated by Trist, Mexico ceded Alta California and New Mexico to the United States. This was known as the Mexican Cession and included current Arizona and New Mexico and parts of Utah, Nevada and Colorado. Mexico also waived all claims to Texas and recognized the Rio Grande as the southern border with the United States. The number of settlers in Alta California, always a minority of the total population, increased slowly, especially in more births than deaths in California's population.
The 1970s saw the end of private passenger railroads in California, the creation of a national passenger railway (Amtrak), and the opening of the BART rail system in the Bay Area. The few owners of these large ranches were inspired by the landowning nobility in Spain and dedicated themselves to maintaining themselves living in great style.Most of the grants were virtually free and usually went to friends and family of the California government. Thus, in the next dozen years, local authorities relaxed restrictions on trade with non-Spanish merchants so that the colony could survive, and Californians became accustomed to contacting sailors, merchants, hunters and trappers from England, France, Russia and, of course, the United States. By then, California was home to a native population now reduced to less than 100,000 and about 14,000 permanent residents.Nicholas Trist was sent to Mexico in 1847 to work with General Winfield Scott to negotiate an agreement in the war between Mexico and the United States.
The possibility of dividing Southern California as a territory or state was rejected by the national government, and this idea had died in 1861 when patriotic fervor swept California after Fort Sumter's attack.Before Alta California became part of Mexico's state, approximately 30 Spanish land grants had already been made throughout Alta California to soldiers of Presidio and government officials as well as some friends and family of Alta California's governors. These grants needed to be direct. Before Gold Rush there was almost no infrastructure in California except for a few small towns, secularized and abandoned missions, and about 500 large ranches (averaging more than 73 km) owned by Californians who had mostly seized Mission's land and livestock.With Mexico's defeat in September 1847, its army fell and its capital city Mexico City surrendered to United States. The Central Pacific Railroad handled almost all cargo across Sierra Nevada Mountains in Northern California.
In San Diego Serra founded first of 21 Spanish missions that extend along California coast.