The Orissa famine of 1866 affected the east coast of India from Madras upwards, an area covering 180,000 miles and containing a population of 47,500,000; the impact of the famine, however, was greatest in Orissa, now Odisha, which at that time was quite isolated from the rest of India. In Odisha, one third of the population died due to famine.
Like all Indian famines of the 19th-century, the Odisha famine was preceded by a drought: the population of the region depended on the rice crop of the winter season for their sustenance; however, the monsoon of 1865 was scanty and stopped prematurely. In addition, the Bengal Board of Revenue made incorrect estimates of the number of people who would need help and was misled by fictitious price lists. Consequently, as the food reserves began to dwindle, the gravity of the situation was not grasped until the end of May 1866, and by then the monsoons had set in.
Efforts to ship the food to the isolated province were hampered because of bad weather, and when some shipments did reach the coast of Odisha, they could not be moved inland. The British Indian government imported some 10,000 tons of rice, which reached the affected population only in September. Although many people died of starvation, more were killed by cholera before the monsoons and by malaria afterwards. In Odisha alone, at least 1 million people, a third of the population, died in 1866, and overall in the region approximately 4 to 5 million died in the two-year period.
The heavy rains of 1866 also caused floods which destroyed the rice-crop in low-lying regions. Consequently, in the following year, another shortfall was expected, and the Government of British India imported approximately 40,000 tons of rice at four times the usual price. However, this time they overestimated the need, and only half the rice was used by the time the summer monsoon of 1867, followed by a plentiful harvest, ended the famine in 1868. In the two years of the famine, the Government of British India spent approximately Rs.9,500,000 on famine relief for 35 million units (i.e. one person per day); a large proportion of the cost, however, was the high price of the imported grain.
Lessons learnt from this famine by the British rulers included "the importance of developing an adequate network of communications" and "the need to anticipate disaster".Indian Famine Codes were slowly developed which were "designed to be put into place as soon as a failure of the monsoon, or other warning-signal, indicated a probable shortage". One early success of this new approach was seen in the Bihar famine of 1873-74 when the famine relief under Sir Richard Temple resulted in the avoidance of almost all mortality.