Juan Bautista Rogers Cooper (born John Rogers Cooper on September 11, 1791, Alderney, British Channel Islands – June 2, 1872, San Francisco, California) was a 19th-century pioneer of California, who held British, Mexican, and finally American citizenship.

[3] After moving to Boston with his mother, he traveled extensively, first attending school in Charleston and then serving as second mate on a missionary trip to the Hawaiian Islands.

[4] Upon his arrival in Monterey, Cooper sold the Rover to the government of newly independent Mexico, which as yet had no ships on the Pacific Coast with which to maintain contact with Alta California.

Along with conversion to Catholicism and marriage into a prominent family, naturalization helped Cooper become accepted in Monterey and obtain land grants.

[6] Cooper saw enormous possibilities for growth in California, and persuaded his half-brother Thomas O. Larkin to relocate from the eastern United States in 1832 to assist him in his business pursuits.

[6] Cooper worked tirelessly with Larkin to strengthen trade with China, England, the U.S., and South America and later help California join the union.

[1][7] Cooper made a number of trips from 1839 to 1844 to the Mexican coast and to the Hawaiian Islands in command of the government-owned Californian, which carried mail, prisoners, and government officials from Monterey to Mexico.

[10] Governor José Figueroa was interested in countering the Russian presence at Fort Ross in Northern California.

Between 1824 and 1836 the Mexicans found during every exploratory effort north of present-day San Rafael and west of Sonoma increasing evidence of Russian presence.

[11] In 1833, Figueroa granted Cooper Rancho El Molino (about 17,892-acre (72.41 km2)) in present-day Sonoma County, California.

[14] In October 1829, Cooper bought 7,000 acres (2,800 ha) of Rancho Bolsa del Potrero y Moro Cojo from Joaquín de la Torre for $2,000.

[1][16][19] Cooper was apparently involved in managing the ranch as early as 1834, when he contracted with Job Dye to raise mules on Rancho El Sur.

)[16][19] Alvarado also granted Cooper Rancho Punta de Quentin in present-day Marin County.

In 1844, Governor Manuel Micheltorena granted Cooper and Pablo de la Guerra Rancho Nicasio, also in Marin County.

[1] The Cooper family ran a cattle ranch and dairy operation on Rancho El Sur, employing Hispanic and Indian vaqueros.

Cooper married 18 year old Martha Brawley, a cousin (once removed) of Abraham Lincoln, at the San Carlos Cathedral.

Their daughter Amelia married Eusebio Joseph Molera, a graduate of the Royal Academy of Engineering in Spain and the first person to obtain a patent for propelling vehicles by use of a storage battery, in 1875.

[24][25] The son John B. H. Cooper built a new home on his portion of Rancho El Sur Ranch but died on June 21, 1899, before he could move in.

In 1928 she sold 5,000 acres (2,000 ha) of the ranch for about $500,000 to businessman Harry Cole Hunt and his wife Jane Selby (née Hayne) of Carmel-by-the-Sea.

He served as a chairman on the U.S. Surveyor General's 1860 survey of the rancho and later was employed as caretaker of Cooper's Monterey home, the Cooper-Molera Adobe.

He documented a chronology of wet and dry weather cycles gathered from samples of living redwoods in the area.

While buying other properties, Cooper was unable to pay some debt, and sold half of his land to John Coffin Jones.

He in turn sold part of his portion of the site to his clerk Nathan Spear, who built a warehouse on the property.

Spear sold part of his property to Manuel Diaz, a prosperous storekeeper and politician, who operated a corner store.

[42] The property contains structures that were built both before and after the main house, reflecting California's Spanish and New England architectural history.

They negotiated with the community stakeholders and formalized a plan to open a cafe, gift store, and events center to fund the site.

It is recognized as a leading example of Spanish building style combined with New England architecture[45] reflecting Monterey's history from 1823 to 1900.