The following is a timeline of the history of San Diego, California, United States.
Before the 19th century
ca. 8000 BCE - 1000 CE – Paleo-Indian groups, such as the La Jolla complex and the San Dieguito complex, arrived in the region and inhabited the area. ca. 1000 CE – Kumeyaay migrate to the San Diego area from the east. Villages such as Kosa'aay are established in the area. 1542 – First European contact with the area, as Juan Rodríguez Cabrillo enters San Diego Bay. 1602 – Second European contact, as Sebastián Vizcaíno maps and names San Diego Bay.
Spanish colonization (1769-1821) 1769 – Presidio of San Diego and Mission San Diego de Alcalá established at the Kumeyaay village of Kosa'aay; first European settlements of Alta California in New Spain. 1774 – Mission is moved from Presidio Hill to current site 6 miles away, near San Diego River 1775 – Kumeyaay Revolt of 1775, Mission San Diego is sacked. 1778 – Pa’mu Incident, Kumeyaay revolt resulting in the first public execution sentence by colonial authorities in California (although the execution did not follow through as planned). 1790 – Population: 189 1795 – Public school opens.
19th century 1800 – 6.5 magnitude Earthquake 1804 – Province of Las Californias divided, the San Diego region becomes part of Alta California. 1812 – Earthquake destroys Mission San Diego de Alcalá, rebuilt the following year 1817 – Mission Dam and aqueduct constructed.
Mexican period (1821–1848) 1821 – Mexico gains its independence from Spain; San Diego becomes part of the Mexican province of Alta California. 1825 – San Diego becomes the unofficial capital of Alta California, under the influence of Governor Jose Maria Echeandia. 1826 – Presidio skirmish kills 28 Kumeyaay natives. 1833 – Mexican secularization act of 1833 closes Mission San Diego de Alcalá. 1834 Mission secularized; Mission lands sold or given to wealthy Californios. Missionized Kumeyaay pressured to abandon coastal regions and move inland. San Diego becomes a pueblo. Richard Henry Dana Jr. visits San Diego as a sailor, later writing about his experiences in the best-selling book Two Years Before the Mast. 1835 – Juan María Osuna is elected the first alcalde (mayor) of San Diego. 1836 – Alta California disestablished and merged with Las Californias under the Siete Leyes. 1837 – First Kumeyaay raid on San Diego. 1838 – San Diego loses pueblo status because of declining population amid increasing hostilities between the Californio settlers and the Kumeyaay, becomes sub-prefecture of Pueblo de Los Ángeles. 1840 – Population: 140. 1842 – Second Kumeyaay raid on San Diego.Connolly, Mike. "Kumeyaay - The Mexican Period". www.kumeyaay.com. Retrieved 2020-10-16. 1844 – Kumeyaay-Quechan blockade reaches the Pacific from the Colorado River, halting southbound overland traffic from San Diego until 1846. 1846–47 Mexican–American War Battle of San Pasqual on December 6–7, 1846 Treaty of Cahuenga ceasefire signed January 13, 1847 1847 – Siete Leyes repealed, reestablishing Alta California and Baja California territories. Baja California territory is granted more land north, placing the provincial border just south of Tijuana.
Late 19th Century (1850s–1890s) 1848 – Treaty of Guadalupe Hidalgo (proclaimed July 4, 1848) transfers San Diego and mostly all of Alta California to the United States of America as part of the Mexican Cession territory, international border drawn closer to San Diego at a parallel "one Spanish league" south of the southernmost point of San Diego Bay. 1850 California is admitted to the United States; San Diego becomes seat of San Diego County; San Diego is granted a city charter by the California legislature. San Diego officially becomes an incorporated city. William Heath Davis proposes "New San Diego" by the bay front, builds a pier and lays out streets, but proposed development is unsuccessful 1851 Herald newspaper begins publication. San Diego Tax Rebellion of 1851 begins, led by Cupeño and Kumeyaay natives after San Diego County charges local natives to pay up an annual $600 in property taxes. Western theatre of the Yuma War opens up in San Diego County. The Movement for State Division of California convenes in San Diego to discuss the secession of Southern California from the rest of California, as the proposed state of Colorado. 1852 Antonio Garra is tried and executed in San Diego. San Diego Tax Rebellion and the Yuma War in San Diego County ends. City goes bankrupt; city charter repealed by legislature; city placed under control of a board of trustees U.S. Army sets aside southern part of Point Loma for military uses, later developed into Fort Rosecrans 1853 – San Bernardino County breaks off from San Diego County. 1855 – Point Loma Lighthouse built. 1857 – The San Antonio–San Diego Mail Line (also known as Jackass Mail) is established, and is acquired by the Butterfield Overland Mail in 1860. 1858 – October: Hurricane. 1859 – San Diego County votes to secede from California to form the Territory of Colorado, voting 207–24 in favor of secession 1861 – The San Antonio–San Diego Mail Line is discontinued due to the American Civil War and the Apache Wars. All interstate commercial mail lines after the civil war would then come through Los Angeles by stage line or San Francisco by steamship until the completion of the San Diego and Arizona Railway in 1919. 1862 – 6.0 magnitude Earthquake 1866 – Louis Rose lays out town of Roseville, later incorporated into San Diego 1867 Alonzo Horton promotes move to "New Town", site of current Downtown. Population: 12. 1868 City reserves of land as City Park, now Balboa Park San Diego Union newspaper begins publication. 1870 Chamber of Commerce established. Horton House hotel in business. 1871 – City and County records are moved from Old Town to New Town, establishing New Town as the city's hub 1872 – San Diego incorporated. 1875 – Ulysses S. Grant sets aside reservation land for several Kumeyaay bands. Second round of reservations established in 1893. 1880 – Population: 2,637; county 8,018. 1881 – The Sun newspaper begins publication. 1882 – San Diego Free Public Library established. Russ High School (now San Diego High School) opens; first high school in the city. YMCA established. 1883-1886 - John J. Montgomery makes successful flights with manned gliders at Otay Mesa, the first controlled flights in a heavier-than-air flying machine in America. 1885 – Santa Fe railway begins operating. 1886 – Horse-drawn streetcar line established downtown. 1887 Ocean Beach founded. San Diego Daily Bee newspaper begins publication. National City & Otay Rail Road begins operating. Electric streetcar line established between Downtown and Old Town. National City is incorporated. 1888 Oceanside and Escondido are incorporated. Sweetwater Dam completed. 1889 City rechartered; mayor-council form of government adopted. Beth Israel synagogue built. 1890 Population: 16,159. Coronado is incorporated. 1892 – San Diego Electric Railway begins operating. 1893 – Riverside County breaks off from San Diego County. 1895 – Evening Tribune newspaper begins publication. 1897 – San Diego State Normal School (now San Diego State University) established. 1898 – Lomaland established by the Theosophical Society in Point Loma. 1899 - The San Diego County Bar Association, a non-profit organisation, was formed. 1900 - Population: 17,700.
20th century 1900s–1940s
1901 – Raja Yoga Academy established at Lomaland. 1903 – Marine Biological Association of San Diego founded; now Scripps Institution of Oceanography. 1904 – Navy Coaling Station established on Point Loma; first navy establishment in the city. 1905 – USS Bennington (PG-4) explodes in the harbor due to a faulty boiler, killing 66 and injuring 46; burial and memorial at what later becomes Fort Rosecrans National Cemetery 1906 – Navy wireless radio station established on Point Loma. 1907 – Imperial County breaks off from San Diego County. 1908 – Great White Fleet visits San Diego. 1909 Scripps Building constructed. Construction begins on Broadway Fountain in Horton Plaza. William Smythe founds San Ysidro, later (1957) annexed to San Diego. 1910 "City Park" renamed Balboa Park. U.S. Grant Hotel built. San Diego Civic Orchestra active. Aero Club established. Population: 39,578; county 61,665. Broadway Fountain completed and dedicated October 15, 1910. 1911 – Chula Vista is incorporated. 1912 February: San Diego free speech fight begins. La Mesa and El Cajon are incorporated. 1913 – Cabrillo National Monument established. 1915 Santa Fe Depot opens. March 9: Panama–California Exposition opens. May: San Diego stadium opens; now Balboa Stadium. 1916 January–February: the "Hatfield flood", a major flood blamed by San Diegans on Charles Hatfield, a rainmaker they had hired. San Diego Zoo Established 1917 Army Camp Kearny established at the site of what would later become Marine Corps Air Station Miramar. Marine Corps Camp Matthews marksmanship range established at the site of what would later become the University of California, San Diego 1919 San Diego and Arizona Railway completed. National Association for the Advancement of Colored People branch established. Holy Cross Cemetery dedicated. 1920 – Population: 74,683; county 112,248. 1921 - U.S. Marine Corps training base commissioned. 1922 U.S. Navy Destroyer Base, San Diego established; now Naval Base San Diego. Rancho Santa Fe settled near San Diego. 1923 Naval Training Center San Diego established. San Diego annexes East San Diego. 1924 – The first United States aircraft carrier began operating out of North Island. 1925 Mission Beach Amusement Center (amusement park) opens. U.S. Naval hospital built. 1926 Star of India is towed into San Diego harbor; later renovated and opened as a museum ship Fine Arts Gallery opens; now the San Diego Museum of Art. 1927 Charles Lindbergh's plane The Spirit of St. Louis is designed and built in San Diego by the Ryan Airline Company. Prudden-San Diego Airplane Company in business; later Solar Aircraft Company, now Solar Turbines. El Cortez Hotel built. 1928 San Diego Municipal Airport dedicated as Lindbergh Field. San Diego Historical Society founded; now the San Diego History Center. 1929 – Fox Theatre dedicated. 1930 – Population: 147,995; county 209,659. 1931 San Diego State College dedicated; formerly San Diego State Normal School, now San Diego State University. New city charter adopted under a council–manager form of government Roberto Alvarez vs. the Board of Trustees of the Lemon Grove School District, ruled that the segregation of Mexican American elementary school children was a violation of California state laws, becoming the first school successful desegregation through the court system in the United States. 1933 – Aztec Brewing Company relocates to city. 1934 Ryan Aeronautical Company in business. Flag of San Diego adopted. 1935 May 29: California Pacific International Exposition opens. Old Globe Theatre established. Consolidated Aircraft Company relocates to city. 1936 San Diego Padres established as a minor league team within the Pacific Coast League. Roman Catholic Diocese of San Diego established. 1937 – U.S. Coast Guard Air Station San Diego commissioned. 1938 – San Diego Civic Center dedicated; now the San Diego County Administration Center. 1940 Marine base Camp Elliott established adjacent to Camp Kearny. Population: 203,341; county 289,348. 1941 – Consolidated Aircraft becomes San Diego's largest employer with 25,000 employees. 1942 Residents of Japanese descent are evicted from San Diego and relocated to internment camps. U.S. Marine Corps Base Camp Pendleton established near city. Japanese submarine I-17 lands secretly at Point Loma before heading north to attack Santa Barbara. 1943