Nagaland, state in extreme northeastern India, bordered on the west and north by Assam state, on the east by Myanmar (formerly known as Burma), on the north by Arunāchal Pradesh state, and on the south by Manipur state. Nagaland is one of India's smallest states, with a total area of 16,579 sq km (6,401 sq mi). The terrain is mountainous, thickly wooded, and cut by deep river valleys. There is a wide variety of plant and animal life. Nagaland has a monsoon climate with generally high humidity; rainfall averages between 1,800 and 2,500 mm (70 and 100 in) a year.

The population of Nagaland was 1,988,636 at the 2001 census, giving the state an average density of 120 persons per sq km (311 per sq mi). The capital is Kohīma, which became famous in World War II as the place where the Japanese advance was halted by Indian and British forces in 1944. The main commercial center is Dimāpur, 74 km (46 mi) from Kohīma, which has a railroad and airport. Society is predominantly tribal and many traditional customs are maintained, such as communal housing for young, unmarried men. The largest tribes are the Angami, Ao, Sema, Konyak, and Chakesang. Tribal structures vary among groups. Traditionally the Konyak had powerful hereditary chiefs while the Ao and Lotha selected councils of elders. In modern times members with a formal education have taken over the roles of the traditional group leaders; these village officials are appointed by the government. The principal languages are Angami, Ao, Chang, Konyak, Lotha, Sangtam, and Sema. British missionaries were active in the region in the 19th century, and today about 90 percent of the population is Christian.

Agriculture employs about 90 percent of the people of Nagaland. Rice and corn are the main crops. However, the state is not self-sufficient in food. Shifting cultivation (also known as slash-and-burn agriculture) is widely practiced. Food needs have caused the fallow, or idle, period to be cut to a couple of years, causing erosion and a loss of soil fertility and crop yields. The forests, which cover about 17 percent of Nagaland, are its most important source of income. There are varied mineral reserves, including oil deposits, but little exploitation. The state has adopted an industrialization program since the 1970s. Dimāpur now has sugar mills, pulp and paper mills, breweries, and a plywood factory. Handloom and handicrafts remain important.