About two-thirds of Nigeria lies in the watershed of the Niger River, which empties in to the Atlantic at the Niger Delta, and its major tributaries: the Benue in the northeast, the Kaduna in the west, the Sokoto in the northwest, and the Anambra in the southeast.
Nigeria is a federal republic modeled after the United States, with executive power exercised by the president. The government of Nigeria is also influenced by the Westminster System model in the composition and management of the upper and lower houses of a bicameral legislature.
The culture of Nigeria is shaped by Nigeria’s multiple ethnic groups. The country has over 50 languages and over 250 dialects and ethnic groups. The three largest ethnic groups are the Hausa-Fulani who are predominant in the north, the Igbo who are predominant in the southeast, and the Yoruba who are predominant in the southwest.