The secularization of California missions from 1834 to 1837 opened great amounts of land throughout California for grants. The area now known as the Livermore Amador Valley had been the grazing land for Mission San Jose's thousands of cattle and sheep since its establishment in 1796. The Mission church property was turned over to the goverment who reduced it to just the land surrounding the church proper. But for some few years earlier the Mexican authorities had been whittling away at mission lands, often in the form of land grants to those who had given exceptional service to the government.

The metes and bounds of a grant were usually determined by natural landmarks, such as trees or geologic features. Generally, surveys were imprecise, relying on two horsemen and a rope of known length. At a given point, one horseman held one end of the rope while the other rode ahead to its end in a predetermined direction. The first horseman then overtook the second, and they kept exchanging places until they reached a final point. The length of the rope and the number of times, give or take a few, the exchange was made provided a distance.

Rancho San Ramon
One of those to whom land was given was Jose Maria Amador whose years of service as a soldier merited him in 1835 a grant of four leagues (a league nominally being 4,400 acres) of mission land. He called it Rancho San Ramon. On a spot northwest of the present intersection of San Ramon Valley Boulevard and Dublin Boulevard, he built his home (destroyed in the 1868 earthquake) near a natural water source called Alamilla Springs (hidden in an apartment complex at that intersection, and still flowing). Amador was one of the few grantees not entirely dependent on the sale of hides and tallow as income. He established facilities employing Indian laborers for tanning leather, making shoes and soap, making saddles and harness, weaving blankets, even manufacturing wagons. With the coming of Americans to the area, Amador took the opportunity to sell the land south of the present Dublin Boulevard to Irishmen Michael Murray and Jeremiah Fallon sometime before 1852, and property to the north to a Mississippian, J. W. Dougherty sometime after. In 1848, with the discovery of gold, he temporarily departed for the Mother Lode country where, with Indian laborers, he mined for gold. Amador County bears Amador's name.

Rancho Santa Rita
Extending east from Foothill Road, with the San Ramon grant on the north and the Valle de San Jose grant on the south, Rancho Santa Rita was given to Jose Dolores Pacheco in 1839. The grant included more than 8,000 acres of excellent grazing land. Pacheco was an absentee landowner: in 1844, his mayordomo (ranch manager), Francisco Solano Alviso probably built the little adobe in 1844 that stands on Foothill Road overlooking the valley. The house is known most recently as Meadowlark Dairy. Rancho Santa Rita won't be forgotten - the Alameda County jail recalls it to memory.

Rancho El Valle de San Jose
When the title to Rancho El Valle de San Jose was finally settled, the total area given the grantees was 64,000 acres, making it one of the largest Mexican land grants given out. The recipients were the Bernals, Jose Agostin, Juan Pablo and their two sisters, one married to Antonio Maria Pico and the other to Antonio Sunol. The grant boundaries extended from the Santa Rita grant on the north to the Calaveras watershed on the south, and as far east as Robert Livermore's Rancho Las Positas. By 1850, the herds of the rancho were estimated at twenty-five thousand cattle, several thousand sheep and a thousand head of horses. By the time the grant was finally patented in 1863, three of the owners had sold their share to Juan Pablo Bernal. The Bernal's were one of the few families to keep their holdings intact, selling them off in "plots" of 100 to 500 acres each for any price they could get. Much of the towns of Livermore and Pleasanton and the intervening gravel pits now occupy the Rancho El Valle de San Jose.

Rancho Las Positas
The fourth and second largest of the Mexican land grants in the Livermore Amador Valley was made to Robert Livermore, a naturalized Mexican citizen of English birth, and Jose Noriega in 1839. Livermore had been living on the property since about 1835. He was as much interested in viticulture and horticulture as he was in cattle and horses: he was the first in this area to plant a vineyard in 1846 and an orchard of pears and olives. Robert Livermore died in 1858 before the the establishment of the town that bears his name.

The first building on his ranch was an adobe dwelling. In 1849 he added a two-story "Around the Horn" house, the first wooden building in the valley. The adobe was in ruins by 1875, but the wooden structure, essentially a "pre-fab", was not torn down until the 1950's. Livermore's became a popular stopping place after the discovery of gold for Argonauts headed for the Mother Lode country, as it was the first night's stopping place from San Jose.

The name, Rancho Las Positas, comes from small springs located about a mile east of North Livermore Avenue that provided him water for irrigating his fields