Rancho Arroyo Seco was a 48,857-acre (197.72 km2) Mexican land grant in the northern San Joaquin Valley, primarily within present-day Amador County, California.
With the cession of California to the United States following the Mexican-American War, the 1848 Treaty of Guadalupe Hidalgo provided that the land grants would be honored.
[5] In 1852 Yorba sold Rancho Arroyo Seco to former Mexican Alta California governor Andrés Pico.
In 1857, Andrés Pico sold Rancho Arroyo Seco to Joseph Moravia Moss, Horace Carpentier, Edward Fitzgerald Beale, and Herman Wohler in 1862.
[6] Neither Yorba or Pico did much to improve the property, and settlers built the towns of Quincy, Muletown, Jackson Valley, and Live Oak.