Pan-Asian explosion in Orange county, California, with numbers up 41pc in 10 years

When the Chinese School in Irvine opened in the 1970s as a home for teaching the language and culture, only 30 students filled a handful of rented classrooms.

Now, it has its own campus, bursting with more than 1,200 pupils. It is a reflection of the explosive growth of Orange county's Asian population, which ranks as the third-largest in the United States, after Los Angeles and Santa Clara counties.

In a sprawling county of three million residents, there are nearly 600,000 Asian Americans, marking a dramatic 41 per cent increase from 2000 to 2010.

Orange county's Asian communities are also developing differently from older ethnic enclaves. Rather than being dominated by one immigrant group, some of the area's communities have a pan-Asian feel, filled nearly equally with Chinese, Korean, Vietnamese and Japanese, often sharing shopping districts and neighbourhoods.

Until recently, the county's most visible Asian cluster was Little Saigon, a once-sleepy central district which had been transformed by Vietnam war refugees into a bustling shopping and dining destination.

Since then, Asian American populations have spread in all directions.