Nicolas Notovitch (1858-1916), a Russian, popularized the notion that Jesus had travelled to India in his The Unknown Life of Jesus Christ. I am linking to the audiobook version and to the PDF copy of his book. This Russian doctor, while traveling through the Himalayas, over the Vale of Kashmir, stayed in a Tibetan convent. There he learned about a Tibetan legend, called The Life of St. Issa, about Jesus’s sojourn in India and Tibet.
Was The Life of St. Issa, and the general proposal of Jesus’s sojourn in India, a deliberate hoax? Here’s a 19th century article arguing that it was just such a fiction: Hoax article
One Swami Abhedananda, however, purported to confirm Notovitch’s evidence. During his travels in the region, he found a Bengali translation of Notovitch’s text (two hundred twenty-four verses). A Russian philosopher Nicholas Roerich (1925) followed suit and corroborated Notovitch’s discovery. (See: Notovitch: Corroborating Evidence )
Here’s the PDF of Notovitch’s work: The Unknown Life of Jesus Christ