Nigeria (nījĭr'ēə) , officially Federal Republic of Nigeria, republic (2005 est. pop. 128,772,000), 356,667 sq mi (923,768 sq km), W Africa. It borders on the Gulf of Guinea (an arm of the Atlantic Ocean) in the south, on Benin in the west, on Niger in the northwest and north, on Chad in the northeast, and on Cameroon in the east. Abuja is the capital and Lagos is the largest city.

Land and People

The Niger River and its tributaries (including the Benue, Kaduna, and Kebbi rivers) drain most of the country. Nigeria has a 500-mile (800-km) coastline, for the most part made up of sandy beaches, behind which lies a belt of mangrove swamps and lagoons that averages 10 mi (16 km) in width but increases to c.60 mi (100 km) wide in the great Niger delta in the east. North of the coastal lowlands is a broad hilly region, with rain forest in the south and savanna in the north. Behind the hills is the great plateau of Nigeria (average elevation 2,000 ft/610 m), a region of plains covered largely with savanna but merging into scrubland in the north. Greater altitudes are attained on the Bauchi and Jos plateaus in the center and in the Adamawa Massif (which continues into Cameroon) in the east, where Nigeria's highest point (c.6,700 ft/2,040 m) is located.
In addition to Abuja and Lagos, other major cities include Aba, Abeokuta, Ado, Benin, Enugu, Ibadan, Ife, Ilesha, Ilorin, Iwo, Kaduna, Kano, Maiduguri, Mushin, Ogbomosho, Onitsha, Oshogbo, Port Harcourt, and Zaria.
Nigeria is easily the most populous nation in Africa and one of the fastest growing on earth. The inhabitants are divided into about 250 ethnic groups. The largest of these groups are the Hausa and Fulani in the north, the Yoruba in the southwest, and the Igbo in the southeast. Other peoples include the Kanuri, Nupe, and Tiv of the north, the Edo of the south, and the Ibibio-Efik and Ijaw of the southeast. English is the official language, and each ethnic group speaks its own language. About half of the population, living mostly in the north, are Muslim; another 40%, living almost exclusively in the south, are Christian; the rest follow traditional beliefs.

Economy

The economy of Nigeria historically was based on agriculture, and more than half of the workforce is still engaged in farming (largely of a subsistence type). The chief crops are sorghum, millet, soybeans, peanuts, cotton, corn, yams, rice, palm products, cacao, and rubber. In addition, poultry, goats, sheep, and cattle are raised. Crop production has fallen in recent years and Nigeria must now import food.
Petroleum is the leading mineral produced in Nigeria; it is found in the Niger delta, in the bights of Benin and Biafra, and on the Bakassi peninsula along the Cameroon-Nigeria border, a disputed area where the two countries have been involved in clashes. (In 2002 the International Court of Justice awarded the peninsula to Cameroon, but the decision has yet to be implemented.) Petroleum production on an appreciable scale began in the late 1950s, and by the early 1970s it was by far the leading earner of foreign exchange. The growing oil industry attracted many to urban centers, to the detriment of the agricultural sector. In the 1980s a decline in world oil prices prompted the government to bolster the agricultural sector. Nonetheless, both refinery capacity and agriculture have not kept pace with population growth, forcing the nation to import refined petroleum products and food. Other minerals extracted include tin, limestone, columbite, coal, low-grade iron ore, and gold.
Industry in Nigeria includes the processing of agricultural goods and the manufacture of textiles, footware, soap, tobacco products, paper, cement, fertilizer, chemicals, and steel. Fishing and forestry are also important. In addition, traditional woven goods, pottery, metal objects, and carved wood and ivory are produced. Nigeria's road and rail systems are constructed basically along north-south lines; the country's chief seaports are Lagos, Warri, Port Harcourt, and Calabar.
Except when oil prices are low, Nigeria generally earns more from exports than it spends on imports. Other important exports include cocoa, rubber, and palm products. The main imports are machinery, chemicals and refined petroleum products, motor vehicles, manufactured consumer goods, and food. The leading trade partners are Great Britain, the United States, Japan, the Netherlands, and France.

Government

Nigeria is governed under the constitution of 1999. The executive branch is headed by a president, who is popularly elected for a four-year term and is assisted by a cabinet. The bicameral legislature consists of a 360-seat house of representatives and a 109-seat senate; all legislators are elected for four-year terms. Parliament convened for the first time in Abuja in Aug., 1999. For administrative purposes, the country is divided into 36 states and a federal capital territory.

History

Early History
Little is known of the earliest history of Nigeria. By c.2000 B.C. most of the country was sparsely inhabited by persons who had a rudimentary knowledge of raising domesticated food plants and of herding animals. From c.800 B.C. to c.A.D. 200 the neolithic Nok culture (named for the town where archaeological findings first were made) flourished on the Jos Plateau; the Nok people made fine terra-cotta sculptures and probably knew how to work tin and iron. The first important centralized state to influence Nigeria was Kanem-Bornu, which probably was founded in the 8th cent. A.D., to the north of Lake Chad (outside modern Nigeria). In the 11th cent., by which time its rulers had been converted to Islam, Kanem-Bornu expanded south of Lake Chad into present-day Nigeria, and in the late 15th cent. its capital was moved there.
Beginning in the 11th cent. seven independent Hausa city-states were founded in N Nigeria—Biram, Daura, Gobir, Kano, Katsina, Rano, and Zaria. Kano and Katsina competed for the lucrative trans-Saharan trade with Kanem-Bornu, and for a time had to pay tribute to it. In the early 16th cent. all of Hausaland was briefly held by the Songhai Empire. However, in the late 16th cent., Kanem-Bornu replaced Songhai as the leading power in N Nigeria, and the Hausa states regained their autonomy. In southwest Nigeria two states—Oyo and Benin—had developed by the 14th cent.; the rulers of both states traced their origins to Ife, renowned for its naturalistic terra-cotta and brass sculpture. Benin was the leading state in the 15th cent. but began to decline in the 17th cent., and by the 18th cent. Oyo controlled Yorubaland and also Dahomey. The Igbo people in the southeast lived in small village communities.