Nagarathar businesspeople are generally Hindus, predominantly originating in the Chettinad region of Tamil Nadu. They have been trading with Southeast Asia since the heyday of the Chola empire, but in the 19th Century they migrated to countries throughout SoutheastAsia.

Nagarathars, also known as Nattukkottai Chettiars, were an important trading class of 19th and 20th century South East Asia and spread to Sri Lanka, Myanmar, Malayasia, Singapore, Java, Sumatra, and Ho Chi Minh City. Changing political and economic situations since that time have caused many of these communities to disappear as their members returned to India or sought other, more hospitable homes.

Chettiars were traditionally involved in occupations like moneylending and wholesale trading. Banks established by Chettiars include the now defunct Bank of Chettinad, and the operational Bank of Madurai, Indian Overseas Bank founded by Shri. M. Ct. M. Chidambaram Chettiar, and Indian Bank founded by Raja Annamalai Chettiar. Nagarathars are known for their philanthropy; building temples, and schools and maintaining them throughout Asia.