This is an unparalleled reference tool for California genealogical research, the most significant aid to have been developed from the U.S. census of 1850. This census was the first to list the name of every individual in the household; it also included California for the first time as a state. The enumerations, however, were not in alphabetical order and, therefore, of little use to the researcher. This present work compensates for the deficiencies of the original enumerations and provides a complete index to the 1850 census of California. Arranged by counties, individuals are listed alphabetically by surname with an indication of their age, sex, race, and birthplace. Altogether approximately 92,000 persons are named.