Tapovan Maharaj (1889-1957)
Tapovan Maharaj is probably well known in today's day and age as Swami Chinmayananda's guru.
There is a very interesting story behind Swami Chinmaya finding his guru. Chinmaya, before he became a saint was a freedom fighter and a journalist. One day, he came across an article in a newspaper where he saw something about Swami Sivananda of the Divine Life Society in Rishikesh. Chinmaya did not believe in Saints and Gurus and saw them as charlatans that needed to be exposed in order to save gullible people. Thinking that he was going to be an undercover reported who would expose Swami Sivananda, he went to Rishikesh. What happened instead was that the compassion of the guru transformed Chinmaya instead. Instead, Swami Chinmaya became a follower of Sivananda. Sivananda had very high regard for a wandering swami in the Himalayas, who happened to be from Kerala as well (Chinmaya's mother tongue). This great guru was Swami Tapovan of the Himalayas.