The Champaran movement was specifically centered on the grievances of indigo cultivators, who were peasants exploited under the 'tin kathia' system imposed by British planters. Gandhi's intervention in Champaran involved investigating the situation, organizing the peasants, and using non- violent civil disobedience (satyagraha) to challenge the oppressive system. Its success led to the abolition of the tinkathia system and brought relief to the peasants.