Tharu (Nepali: थारू, Thārū) are an ethnic group indigenous to the Terai -- the southern foothills of the Himalayas in Nepal and India. They are considered to be the direct discendents of the Gautama Buddha.^{[citation needed]} Anthropologist Prof Dor Bahadur Bista, Balaram Gharti Magar and many scholars support the logic Suddhodhana being Tharu king of Kapilvastu, Lumbini-the birth place of Buddha, Nepal. Archealogical findings have also been supporting that Tharu people were living in that area for quite long time. The Tharus are recognized as an official nationality by the Government of Nepal.

The Tharu were famous for their ability to survive in the most malarial parts of the Terai that were deadly to outsiders. In 1902 a British observer noted, "Plainsmen and paharis generally die if they sleep in the Terai before November 1 or after June 1.", although others thought the Tharu weren't totally immune.

Contemporary medical research comparing Tharu with other ethnic groups living nearby found an incidence of malaria nearly seven times lower among Tharu. The researchers believed such a large difference pointed to genetic factors rather than behavioral or dietary differences. This was confirmed by follow-up investigation finding genes for thalassemia in nearly all Tharu studied.