The Champaran region is located in northern Bihar, between the Gandaki River and the Nepalese border.
It is now divided into two provinces: eastern and western Champaran.
The Champaran area is well-known for being the site of Mohandas K. Gandhi's first successful satyagraha (nonviolent struggle) against British authority.
The province was mainly agricultural at the time, as it still is now, with the majority of the people living in poverty.
Farmers had historically set aside a part of their property for producing indigo, which they would then rent to the landlords.
The development of a far cheaper synthetic indigo shattered this arrangement.
The landlords reacted by ordering the tenants to cease producing indigo, but then proceeded to increase the rent on their property, based on a long-standing agreement that permitted them to do so if a renter did not produce indigo.
The unrest started in 1912, but it was not until 1917 that Gandhi arrived.
After a nearly year-long effort, the tenants were able to get concessions from the landlords, including a promise of no future rent increases and a 25% refund on past hikes.
For additional detail, see Mohandas K. Gandhi's An Autobiography, published in 1993; Louis Fischer's Gandhi, published in 1954, provides a more accessible, though incomplete, narrative.
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