Generally, it is said that on 12th April 1919, Rabindranath Tagore wrote a letter to Gandhiji in which he addressed Gandhiji as 'Mahatma'.
However, some scholars believe that in the year 1915 Razvan Jivaram Kalidas had addressed Gandhi as 'Mahatma'. While some believe that Rabindranath Tagore was the first person who called him Mahatma. The truth is given to the whole world and the teachings of non-violence, Mahatma Gandhi was a major political and spiritual leader of the country's freedom movement. Gandhiji used to always say that if someone slaps you, instead of doing violence in such a way, his second cheek should be forwarded. He believed that the person in front of our humble will surely melt at one or the other day.
On the path of truth and non-violence, he not only rebelled against the British but by making his weapon to truth and non-violence, he forced the British rule so much that he had to leave India. Gandhiji has not only taught Indians to the whole world but to win the war without any violence can be won.
"All The best"