Skip County Header
Click a decade to view.
September 9, 1850
First State census: Contra Costa County---722; Santa Clara County---3,502
May 4, 1852
Act to incorporate the City of Oakland.
March 10, 1853
Petition to create Alameda County, from parts of Contra Costa and Santa Clara counties.
March 26, 1853
Act of Incorporation of Alameda County.
April 6, 1853
Act of Incorporation signed by Governor John Bigler.
June 6, 1853
County is divided into judicial townships for the first time.
April 4, 1854
Post office in San Lorenzo established. Albert E Crane is the first postmaster.
April 19, 1854
Town of Alameda incorporates.
Town of San Leandro was founded of the sole, specific purpose of housing the seat of Alameda County.
January 7, 1856
Coal mining begins in Corral Hollow (later Tesla).
February 6, 1856
County seat moves to San Leandro.
August 16, 1856
Gazette, first San Leandro newspaper, begins publication.