Mohandas Karamchand Gandhi, was a proponent of Ahimsa or non-violence. Inspiring a generation of Indians towards Ahimsa, helped India in gaining independence from British rule mostly without bloodshed. Though not solely responsible for Indian freedom, is considered to be a major driver of people towards freedom movement. Lived like a sage, and was murdered by ReligiousFanatics soon after independence.
He is often referred to as the Mahatma (The Great Soul!)