Independent Federation and First Republic (1960–1966)

Nigeria gained independence from the United Kingdom as a Commonwealth Realm on 1 October 1960. Nigeria's government was a coalition of conservative parties: the Nigerian People's Congress (NPC), a party dominated by Northerners and those of the Islamic faith, and the Igbo and Christian-dominated National Council of Nigeria and the Cameroons (NCNC) led by Nnamdi Azikiwe. Azikiwe became Nigeria's maiden Governor-General in 1960. The opposition comprised the comparatively liberal Action Group (AG), which was largely dominated by the Yoruba and led by Obafemi Awolowo.^[49] The cultural and political differences between Nigeria's dominant ethnic groups – the Hausa ('Northerners'), Igbo ('Easterners') and Yoruba ('Westerners') – were sharp.
An imbalance was created in the polity by the result of the 1961 plebiscite. Southern Cameroon opted to join the Republic of Cameroon while Northern Cameroons chose to remain in Nigeria. The northern part of the country was now far larger than the southern part. In 1963, the nation established a Federal Republic, with Azikiwe as its first president. When elections were held in 1965, the Nigerian National Democratic Party came to power in Nigeria's Western Region.

Civil war (1967–1970)

Main article: Nigerian Civil War

The Republic of Biafra in June 1967, when it declared its independence from the rest of Nigeria

The disquilibrium and perceived corruption of the electoral and political process led, in 1966, to back-to-back military coups. The first coup was in January 1966 and was led by Igbo soldiers under Majors Emmanuel Ifeajuna and Chukwuma Kaduna Nzeogwu. The coup plotters succeeded in murdering Prime Minister Abubakar Tafawa Balewa, Premier Ahmadu Bello of the Northern Region and Premier Ladoke Akintola of the Western Region. But, the coup plotters struggled to form a central government. President Nwafor Orizu handed over government control to the Army, then under the command of another Igbo officer, General JTU Aguiyi-Ironsi.
Later, the counter-coup of 1966, supported primarily by Northern military officers, facilitated the rise of Lt. Colonel Yakubu Gowon to head of state. Tension rose between North and South; Igbos in Northern cities suffered persecution and many fled to the Eastern Region.
In May 1967, the Eastern Region declared independence as a state called the Republic of Biafra, under the leadership of Lt. Colonel Emeka Ojukwu.^[50] The Nigerian Civil War began as the official Nigerian government side (predominated by soldiers from the North and West) attacked Biafra (Southeastern) on 6 July 1967 at Garkem. The 30-month war, with a long siege of Biafra and its isolation from trade and supplies, ended in January 1970.^[51] Estimates of the number of dead in the former Eastern Region are between 1 and 3 million people, from warfare, disease, and starvation, during the 30-month civil war.^[52]
France, Egypt, the Soviet Union, Britain, Israel, and others were deeply involved in the civil war behind the scenes. Britain and the Soviet Union were the main military backers of the Nigerian government while France and others aided the Biafrans. Nigeria used Egyptian pilots for their air force.^[53][54]

Military juntas (1970–1999)

Main article: Nigerian military juntas of 1966–1979 and 1983–1998

Olusegun Obasanjo was a military president who ruled the country from 1976 to 1979.

During the oil boom of the 1970s, Nigeria joined OPEC and the huge oil revenues it was generating enriched the economy. Despite these revenues, the military government did little to improve the standard of living of the population, help small and medium businesses, or invest in infrastructure. As oil revenues fueled the rise of federal subsidies to states, the federal government became the centre of political struggle and the threshold of power in the country. As oil production and revenue rose, the Nigerian government became increasingly dependent on oil revenues and on international commodity markets for budgetary and economic concerns. It did not develop alternate revenue sources in the economy for economic stability. That spelled doom to federalism in Nigeria.^[55]
Beginning in 1979, Nigerians participated in a return to democracy when Olusegun Obasanjo transferred power to the civilian regime of Shehu Shagari. The Shagari government became viewed as corrupt by virtually all sectors of Nigerian society. In 1983 the inspectors of the state-owned Nigerian National Petroleum Corporation (NNPC) began to notice "the slow poisoning of the waters of this country."^[56] The military coup of Muhammadu Buhari shortly after the regime's re-election in 1984 was generally viewed as a positive development.^[57] Buhari promised major reforms, but his government fared little better than its predecessor. His regime was overthrown by another military coup in 1985.^[58]
The new head of state, Ibrahim Babangida, declared himself president and commander in chief of the armed forces and of the ruling Supreme Military Council. He set 1990 as the official deadline for a return to democratic governance. Babangida's tenure was marked by a flurry of political activity: he instituted the International Monetary Fund's Structural Adjustment Program (SAP) to aid in the repayment of the country's crushing international debt. At the time most federal revenue was dedicated to servicing that debt. He enrolled Nigeria in the Organisation of the Islamic Conference, which aggravated religious tensions in the country.^[59]
Babangida survived an abortive coup, then postponed a promised return to democracy to 1992. Free and fair elections^{[citation needed]} were finally held on 12 June 1993, the first since the military coup of 1983, with a presidential victory for Moshood Kashimawo Olawale Abiola of the Social Democratic Party, who gained some 58% of the votes, defeating Bashir Tofa of the National Republican Convention.^[60] However, Babangida annulled the elections, leading to massive civilian protests which effectively shut down the country for weeks. Babangida finally kept his promise to relinquish office to a civilian government, but not before appointing Ernest Shonekan head of an interim government.^[61] Babangida's regime has been considered the most corrupt, and responsible for creating a culture of corruption in Nigeria.^[62]
In late 1993 Shonekan's caretaker regime was overwhelmed by the military coup of General Sani Abacha, who used military force on a wide scale to suppress the continuing civilian unrest. He shifted money to offshore accounts in western European banks and defeated coup plots by bribing army generals. In 1995 the government hanged environmentalist Ken Saro-Wiwa on trumped-up charges in the deaths of four Ogoni elders. Lawsuits under the American Alien Tort Statute against Royal Dutch Shell and Brian Anderson, the head of Shell's Nigerian operation, settled out of court with Shell continuing to deny liability.^[63]
Several hundred million dollars in accounts traced to Abacha were discovered in 1999.^[64] The regime came to an end in 1998, when the dictator died in the villa. His successor, General Abdulsalami Abubakar, adopted a new constitution on 5 May 1999, which provided for multiparty elections. On 29 May 1999 Abubakar transferred power to the winner of the elections, Obasanjo, who had since retired from the military.^[65]

Democratisation (1999–)

Bida Emirate durbar festival, 2001

Nigeria regained democracy in 1999 when it elected Olusegun Obasanjo, the former military head of state, as the new President of Nigeria. This ended almost 33 years of military rule (from 1966 until 1999), excluding the short-lived second republic (between 1979 and 1983) by military dictators who seized power in coups d'état and counter-coups during the Nigerian military juntas of 1966–1979 and 1983–1998. Although the elections which brought Obasanjo to power in 1999 and again in 2003 were condemned as unfree and unfair, Nigeria has shown marked improvements in attempts to tackle government corruption and to hasten development.
Ethnic violence for control over the oil-producing Niger Delta region and inadequate infrastructures are some of the issues in the country. Umaru Yar'Adua of the People's Democratic Party (PDP) came into power in the general election of 2007. The international community has been observing Nigerian elections to encourage a free and fair process, and condemned this one as being severely flawed.^[66]
Yar'Adua died on 5 May 2010. Dr. Goodluck Jonathan was sworn in as Yar'Adua's replacement on 6 May 2010,^[67] becoming Nigeria's 14th Head of State, while his vice-president, Namadi Sambo, an architect and former Kaduna State governor, was chosen on 18 May 2010, by the National Assembly. His confirmation followed President Jonathan's nomination of Sambo to that position.^[68][69]
Goodluck Jonathan served as Nigeria's president until 16 April 2011, when a new presidential election in Nigeria was conducted. Jonathan of the PDP was declared the winner on 19 April 2011, having won the election with a total of 22,495,187 of the 39,469,484 votes cast, to stand ahead of Muhammadu Buhari from the main opposition party, the Congress for Progressive Change (CPC), which won 12,214,853 of the total votes cast.^[70] The international media reported the elections as having run smoothly with relatively little violence or voter fraud, in contrast to previous elections.^[7]
In the March 2015 election, Muhammadu Buhari defeated Goodluck Jonathan by roughly 2 million votes. Observers generally praised the election as being fair. Jonathan was generally praised for conceding defeat and limiting the risk of unrest.^{[71][72][73][74]}