The Great Salt March of 1930 was lead by Gandhi.
What makes you think he did? I am searching the biography of Gandhi on Wikipedia, which is quite thorough, for the word "religion", and it doesn't mention anything about him changing his religion.
he was a hindu.
Hinduismhindu
He is a saint of every religion to some.
Hindu Brahmin
Gandhi
He opposed Gandhi's program of tolerance for all creeds and religion
he was a jainGhandi was a Hindu.Hinduism
Mahatma Gandhi lead the march on Dandi.
Mohandas gandhi/aka: mahatma gandhi
A paper on the Boston University website claims that Gandhi was brought up as a Hindu as that was the religion that his mother and other family members practiced.