Indigo is a colorfast, plant-based dye that can be produced from a number of different plants, but it was primarily found in Indigofera, a tropical plant that was cultivated and became a staple agricultural crop. There are three steps to the traditional process of extracting the dye from the plant. First the leaves are fermented in a steeping vat. Then a liquid is extracted and oxidized, and from that, a blue solid forms in the bottom of the vat that is collected and dried. In the 19th century most indigo was made in British-run factories in India.
By the end of the eighteenth century, the demand for Indian indigo grew further and Britain began to industrialize. Supplies from the West Indies and America collapsed for a variety of reasons and the production of indigo in the world unexpectedly fell by half between 1783 and 1789. Cloth dyers in Britain now desperately looked for new sources of indigo supply.
The net result was the British turned to Indian peasants. In the later part of the eighteenth century indigo cultivation in Bengal grew rapidly and Bengal indigo dominated the world market and India accounted for 30 per cent of the indigo imported into Britain in 1788 and roughly 95% 1n 1810.
Indigo was introduced in large parts of Burdwan, Bankura, Birbhum, North 24 Parganas, and Jessore (present Bangladesh). The indigo planters to get the peasants trapped persuaded them to plant indigo instead of food crops on their own lands with loans, called dadon provided by them. The poor farmers had to cough up high interest rate on the loan. The indigo planters managed to get support from the local landlords/ zamindars to back them up.
Attracted by the prospects of inherent high profits, numerous Scotsmen and Englishmen came to India and became planters. Those who had no money to produce indigo could get loans from the Company and the banks. As usual the British and others were harsh and exploited the innocent and duty-bound indigo workers using loan as a bait.
Soon after a bumper harvest each time they would offer money to the peasants not as an incentive or bonus but as a loan in the form of ''advance'' – a sort of never ending cycle of obligation from which they could not escape; a permanent entanglement. While their fat pockets swelled, poor Indian farmers stomach further shrank. The British boss wanted to make a bundle without toiling. Not content with this trap, they forced people to work long hours on the fields. Their silent pain and resentment reached the limits of tolerance level and in March,1859 thousands of peasants refused to work. When the situation became explosive, the Indigo Commission set up by the British ruled that the workers have a right to continue the job and the employers have no right to interfere with their freedom of choice – whether to work or not. However, the commission ruled that workers who are on contract must complete their obligation. In the later years new dyes replaced Indigo and its market declined soon.