Gautam, 92, also known as the historian of Dang for his work on Tharu culture, was ill for last 10 years due to cancer.
Gautam, the first author to write about history of Tharu community, also contributed in establishment of Nepal Sanskrit University. He published more than a dozen books on Dang valley and Tharu people.
He participated in the armed movement in 1951 as a cadre of Nepali Congress.
On Saturday morning, his last rites were performed in presence of Maoist CA member Shiva Raj Gautam and Press Council of Nepal chair Narayan Prasad Sharma.
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