Which provinces do overseas Chinese in Southeast Asia come from?

Fujian, Guangdong, Guangxi and Hainan.

If you want to know the history of Chinese in Southeast Asia, you can watch the TV series Lower Nanyang.

Most of the Chinese in Southeast Asia are descendants of Chinese laborers who went to Southeast Asia to work as coolies in the late Qing Dynasty and early Republic of China. Now, China people who emigrated to Southeast Asia and overseas Chinese living in Southeast Asia are all over the country.