- Total 20,105 sq mi (52,070 km2)
- Land 20,057 sq mi (51,950 km2)
- Water 48 sq mi (120 km2)
Highest elevation 11,503 ft (3,506 m)
Population (April 1, 2010)
- Total 2,035,210
- Estimate (2016) 2,140,096
- Density 100/sq mi (39/km2)
Spanish Missionaries from Mission San Gabriel Arcángel established a church at the village of Politania in 1810. Father Francisco Dumetz named the church San Bernardino on May 20, 1810, after the feast day of St. Bernardino of Siena. The Franciscans also gave the name San Bernardino to the snowcapped peak in Southern California, in honor of the saint and it is from him that the county derives its name. In 1819, they established the San Bernardino de Sena Estancia, a mission farm in what is now Redlands.
Following Mexican independence from Spain in 1821, Mexican citizens were granted land grants to establish ranchos in the area of the county. Rancho Jurupa in 1838, Rancho Cucamonga and El Rincon in 1839, Rancho Santa Ana del Chino in 1841, Rancho San Bernardino in 1842 and Rancho Muscupiabe in 1844.
Following the purchase of Rancho San Bernardino, and the establishment of the town of San Bernardino in 1851 by Mormon colonists, San Bernardino County was formed in 1853 from parts of Los Angeles County. Some of the southern parts of the county’s territory were given to Riverside County in 1893.