The San Diego County Fair began a tradition of annual themes starting in 1980, when the Fair celebrated 100 years. The themes were agricultural in nature until 1998, when the celebration of California's Sesquicentennial lent itself to a theme exhibit on the state's history.
The Fair has been known by four names during its history: The San Diego County Fair from 1880 to 1953 and from 2002 to present; as the Southern California Exposition and San Diego County Fair from 1954 to 1969; as the Southern California Exposition from 1970 to 1982; and as the Del Mar Fair from 1983 through 2001. These names are sometimes reflected in the theme.