California has long been the ultimate melting pot, with the majority of its population coming from outside the state.

Dust Bowl emigres, Asian railroad workers, high-tech entrepreneurs, Mexican laborers and war refugees from around the globe flocked to California. The majority migrant population filled the state's myriad labor needs, challenged the schools with a cacophony of new languages and roiled its politics with immigration debates.

But, in a dramatic demographic shift, California's narrative as the nation's quintessential immigrant state is giving way to a new reality.

For the first time since the 19th century Gold Rush, California-born residents now make up the majority statewide and in most counties, according to a USC study released Wednesday. And experts predict even Los Angeles -- long a mecca for new immigrants -- will become majority California-born by the time the 2010 census is completed.

"Home-grown Californians are the anchor of our economic future," said Dowell Myers, a USC urban planning and demography professor who coauthored the study. "But people are living in the past. They still think we are fighting off hordes of migrants."

The study showed that California's share of foreign-born residents grew from 15.1% in 1980 to a peak