There are about 145 Buddhist centers in Los Angeles County and an estimated 70,000 practicing adherents. Buddhism was introduced into Los Angeles County in the early 20th Century by Japanese immigrants. The oldest Buddhist temple in Los Angeles, the Nishi Hongwanji Temple, was built in 1925. The structure is now part of the Japanese American National Museum.
According to Dr. Diana Eck, Professor of Comparative Religion and Indian Studies at Harvard University, Los Angeles, with its Thai, Korean, Sri Lankan, Vietnamese, Zen, Chinese, and Japanese Buddhist communities, has become the most complex Buddhist city in the world.
According to a December 1993 Los Angeles Times article, comparative religion scholars and demographers see Los Angeles becoming a capital of American Buddhism in the 21st Century.
The Hsi Lai Temple, located in the hills of Hacienda Heights, was inaugurated in November 1988 and became the largest Buddhist monastery in the United States.