He was on the train in the first class as an Indian attorney. He was done with the train even though he had a ticket. This made him realize the unfairness towards Indian people.
DDuring World War I, Gandhi had supported the British in the hope of winning partial autonomy for India, but after the Amritsar Massacre he became convinced that India should accept nothing less than full independence. To achieve this end, Gandhi began organizing his first campaign of mass civil disobedience against Britain’s oppressive rule.
The British government tax the Indians for salt.Gandhi and his followers were not happy with that so they decided to take action.They decided to have a non-violent march for 24 days. This resulted in nearly 60,000 arrests,including Gandhi.