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California: Local History & Genealogy Resource Guide

Compiled by reference specialists at the Library of Congress, this guide identifies key print and online resources for pursuing family history, as well as state, county and municipal historical research, for the state of California.


The Unique Map of California 1888. Library of Congress Geography and Map Division.

Once the home of more than 70 distinct ethnic groups, California's indigenous population was decimated by European and Asian diseases introduced by new colonizers. California has been governed by Spain, Mexico, and most recently by the United States. Alta California was annexed by the United States in 1848, just before gold was discovered there. Statehood was granted in 1850. New populations in the 19th century included Russian, Chinese, Europeans, U.S. citizens, and Japanese. Industries include agriculture, entertainment, technology, aerospace, and more. The population has boomed throughout the 19th and 20th centuries.

This guide offers a selection of resources and strategies for California local history and genealogy research. These include the print and digital collections of the Library of Congress, as well as external repositories and web sites key to finding forebears in the Golden State.

About Local History & Genealogy Reference Services

The Library of Congress has one of the world's premier collections of U.S. and foreign genealogical and local historical publications, numbering more than 50,000 compiled family histories and over 100,000 U.S. local histories. The Library's genealogy collection began as early as 1815 with the purchase of Thomas Jefferson's library.