Question

who call Gandhi as Mahatma Gandhi at first and where
​

Answer 1

According to some authors Rabindranath Tagore is said to have used on March 6, 1915, this title for Gandhi. Some claim that he was called Mahatma by the residents of Gurukul Kangadi in April 1915, and he in turn called the founder Munshiram a Mahatma (who later became Swami Shraddhananda).