He was born Kedarnath Pande on 9 April 1893 to an Orthodox Hindu Bhumihar family in Azamgarh district, in Eastern Uttar Pradesh. As his mother died at the age of twenty-eight and his father at the age of forty-five, he was brought up by his grandmother. His earliest memories as recorded by him were of the terrible famine in 1897. At age 9, he ran away from home in order to see the world, but later returned.
His travels took him to different parts of India, including Ladakh, Kinnaur, and Kashmir. He also covered several other countries including Nepal, Tibet, Sri Lanka, Iran, China, and the former Soviet Union. While traveling, he mostly used surface transport, and he went to certain countries clandestinely, like Tibet where he went disguised as a Buddhist monk. He made several trips to Tibet and brought from there valuable manuscripts of Pali and Sanskrit, several books and paintings. Most of these formed a part of the libraries of Vikramshila and Nalanda Universities and were taken to Tibet by fleeing Buddhist monks during 12th century and onwards when the invading armies had destroyed these universities. Some accounts state that Rahul Sankrityayan employed twenty-two mules to bring back the loads of part of these materials, from Tibet to India.
In honour of him, Patna Museum, Patna, has a special section, where a number of these and other items have been displayed.
Sankrityayan was married when very young and never came to know anything of his child-wife. Accepting an invitation for teaching Buddhism at Leningrad University during his stay in Soviet Russia a second time, he came in contact with a Mongolian scholar Lola (Ellena Narvertovna Kozerovskaya). She could speak French, English, and Russian and write Sanskrit. She helped him in working on Tibetan- Sanskrit dictionary. Their attachment ended in marriage and birth of son Igor. Mother and son were not allowed to accompany Rahul to India after completion of his assignment.
Late in life, he married Dr. Kamala, an Indian Nepali lady and had a daughter (Jaya) and a son (Jeta). He accepted a teaching job at a Sri Lankan University, where he fell seriously ill. Memory loss, diabetes, high blood pressure and a mild stroke struck him. He died in Darjeeling in 1963.
Sankrityayan was a multilingual linguist, well versed in several languages and dialects, including Hindi, Sanskrit, Pali, Bhojpuri, Urdu, Persian, Arabic, Tamil, Kannada, Tibetan, Sinhalese, French and Russian. He was also an Indologist, a Marxist theoretician, and a creative writer. He started writing during his twenties and had written around 150 books and dissertations.