The historic rancho building dates from prior to 1844, when John Temple constructed a single story ranch building after marrying an heir of the Nieto family, the original recipients of the land grant in 1784. John Temple later sold the 27,000-acre property to Bixby, Flint and Company. The Bixby family lived on the rancho and raised sheep there until 1881. It was remodeled in 1930 and a new generation of Bixby family members lived in the house until 1955, when it was donated to the city.
Today, the museum is operated by the Rancho Los Cerritos Foundation, a nonprofit organization, in partnership with the city of Long Beach. It operates as a museum and offers tours and many programs throughout the year.
More information is available at their website.