In 1960 Great Britain granted Nigeria independence. The following year, the northern part of British Cameroons, a United Nations trust territory, voted to become part of Nigeria. The nation became a republic in 1963.

From the time Nigeria received independence, ethnic and religious differences threatened to split the country. Friction between the Ibos in the east and the politically dominant Hausas in the north increased after the national elections of 1964. In 1966 a group of Ibo military officers overthrew the civilian government. They were in turn overthrown by Hausa military leaders.

In 1967 the southeastern region, the homeland of the Ibos, seceded, declaring itself the Republic of Biafra. Civil war followed. By the end of 1968 federal troops held most of Biafra. The Ibos held out for a year in a small, crowded sector where close to a million died of starvation. They surrendered in 1970, and the Nigerian government took steps to reunite the country. Military control of the government continued, however.

Recovery after the civil war was rapid. The economy was spurred by increases in both oil production and international oil prices during the 1970's.

In 1979, civilian rule was restored, but the new leaders mismanaged the country's economy, and wasteful spending and corruption became severe problems. The government was overthrown in 1983 by military leaders. The new regime abolished many basic freedoms, and in 1985 a coup led by Major General Ibrahim Babangida brought a more liberal military government to power.

Babangida became president and promised a return to civilian rule. Attempts to establish democratic rule foundered in 1989 due to conflict between Muslims and Christians. A new attempt failed in 1993 because of conflict between the political parties and Babangida. In August, 1993, Babangida stepped down and an interim government was formed. In November, General Sani Abacha seized power and established a dictatorship. In 1995 Ken Saro Wiwa, an internationally prominent writer and environmental activist, was arrested and hanged along with several others. In response, the members of the Commonwealth of Nations voted to expel Nigeria.

In 1998 Abacha died and General Abdulsalami Abubakar took power. He began negotiations with opposition leaders and freed most political prisoners. In 1999 civilian rule was restored and General Olusegun Obasanjo was elected president. Nigeria was readmitted to the Commonwealth in 1999. Free from military rule, Muslim majority states in the north adopted strict Islamic law in 2000, resulting in an escalation in violence between Christians and Muslims.

Nigerians voters elected the governor of the state of Katisina, Umaru Yar'Adua, as the country's president in April, 2007. However, opponents condemned the election. Protests ensued, resulting in about 200 deaths.