Year | Date | Event |
1901 | | Anglo-Aro war: The war began. The Aro Confederacy began to decline. (to 1902) |
1902 | | Anglo-Aro war: The war ended. |
1903 | January | Capture of Kano |
| The British conquered most of Northern Nigeria, including the Sokoto Caliphate. |
1905 | | The British conquest of Southern Nigeria ended. |
1906 | 1 May | Colonial Office amalgamates Lagos Colony with Southern Nigeria Protectorate. |
1908 | | German-owned Nigerian Bitumen Company began searching for petroleum off coast.[11] |
| Protests against water fees in Lagos, encouraged by nationalistic journalism of Herbert Macaulay.[2] |
1912 | | Lord Frederick Lugard, Governor of Northern Nigeria, established a system of indirect rule. Creation of Southern Nigeria Civil Service Union; later, Nigerian Civil Servants' Union.[2] |
1914 | January | Northern Nigeria and Southern Nigeria were amalgamated into Nigeria. British Crown gained monopoly rights over mineral extraction. |
| Nigerian soldiers fight under British command in World War I.[2] |
1918 | | The Adubi War is fought in Egba Land. |
1920 | | National Congress of British West Africa founded in Accra. |
1922 | | Clifford Constitution. |
1925 | | West African Students' Union. |
1928 | April | British begin direct taxation. |
1929 | 14 October | New governor implements plans to expand taxation. |
November | "Women's War": Widespread revolt against taxation. |
1931 | | Founding of Nigeria Union of Teachers.[2] |
1936 | | Founding of Nigeria Youth Movement.[2] |
1937 | | Shell D'Arcy Petroleum Development Company of Nigeria (later Shell-BP) granted petroleum exploration rights.[11] |
1944 | | National Council of Nigeria and the Cameroons founded by Nnamdi "Zik" Azikiwe.[2] |
1945 | | Countrywide general strike.[2] |
| Adoption of first Ten Year Plan for economic development.[2] |
1946 | | Nigeria entered a period of decolonization and growing Nigerian nationalism. |
1950 | | A conference of northern and southern delegates was held in Ibadan. |
1951 | | MacPherson Constitution. |
| Yoruba-aligned Action Group founded; headed by Obafemi Awolowo.[2] |
1953 | 1 May | Northern vs. Southern violence breaks out in the Northern city of Kano. |
1956 | | Shell-BP expedition makes first discoveries of major petroleum deposits, at Olobiri and Afam.[11] |
1957 | | Nigeria held a Constitutional conference. |
1959 | | Nigeria holds its first national election to set up an independent government. Northern politicians won a majority of seats in the Parliament. |
| 1959 Petroleum Profits Tax Ordinance establishes 50–50 split of oil revenues between corporation and government. Socony Mobil receives offshore oil license.[11] |
1960 | | The period of nationalism and decolonization ended. |
| Tiv uprising. |
1 October | Nigeria gained independence from Britain under Prime Minister Tafawa Balewa and President Nnamdi Azikiwe. |
1961 |
11 February |
A referendum is held in the British Cameroons, resulting in the Northern Cameroons joining Nigeria and the Southern Cameroons joining Cameroon. |
1962 | | Tennessee Nigeria receives offshore oil license. |
1963 | 1 October | Nigeria severed its remaining ties to Britain, marking the birth of the Nigerian First Republic. |
| Amoseas and Gulf receive offshore oil licenses.[11] |
1964 | 1 December | National parliamentary election. |
| SAFRAP and AGIP receive offshore oil licenses. |
| Another Tiv uprising heavily suppressed by police. |
1965 | | Elections held in Western Region. |
Autumn | Refinery completed at Port Harcourt; owned 60% by Federal Government, 40% by Shell-BP.[11] |
1966 | 15 January | A military coup deposed the government of the First Republic. Balewa, Premier of Northern Nigeria Ahmadu Bello, and Finance Minister Festus Okotie-Eboh, were assassinated. |
16 January | The Federal Military Government was formed, with General Johnson Aguiyi-Ironsi acting as head of state and Supreme Commander of the Federal Republic. |
23 February | Isaac Adaka Boro declared the secession of the "Niger Delta Republic". The secession was crushed by Ojukwu and 159 men were killed. |
29 July | A counter-coup by military officers of northern extraction deposed the Federal Military Government. Aguiyi-Ironsi and Adekunle Fajuyi, Military Governor of the Western Region, were assassinated. General Yakubu Gowon became President. |
1967 | | Killings of people of Eastern Nigerian origin claimed the lives of many thousands mostly Christian Igbo people. This was carried out by the Muslim Hausa and Fula people. This triggered a migration of the Igbo back to the East. |
27 May | Gowon announces further subdivision of Nigeria, into twelve states. These include subdivision of the Eastern Region which will undermine its political power. |
30 May | Nigerian-Biafran War: General Chukwuemeka Odumegwu Ojukwu, Military Governor of Eastern Nigeria, declared his province an independent republic called Biafra. |
1970 | 8 January | Ojukwu fled into exile. His deputy Philip Effiong became acting President of Biafra |
15 January | Effiong surrendered to Nigerian forces. Biafra was reintegrated into Nigeria. |
1971 | | Nigeria joins Organization of Petroleum Exporting Countries.[2] |
1973 | 22 January | A plane crashed in Kano, Nigeria, killing 176 people. |
1975 | 29 January | General Yakubu Gowon was overthrown in a bloodless coup. General Murtala Mohammed became Head of State. |
1976 | 13 February | Mohammed was assassinated on his way to work. His deputy, Lieutenant-General Olusegun Obasanjo, became Head of State and set a date to end military rule. |
1979 | | Shehu Shagari won election to the Executive Presidency of the American-style Second Republic. |
1 October | Shagari was sworn in as President. |
1983 | | Shagari won reelection. |
31 December | Shagari's government was ejected from power in a palace coup, marking the end of the Second Republic. General Muhammadu Buhari became Head of State and Chairman of the Supreme Military Council of Nigeria. |
1984 | 17 April | The Buhari regime promulgated Decree No. 4, the "Public Officer's Protection Against False Accusation" Decree, which made it an offence to ridicule the government by publication of false information. |
1985 | August | Buhari was overthrown in a palace coup. General Ibrahim Babangida became Head of State and President of the Armed Forces Ruling Council of Nigeria. |
1990 | April | Middle Belt Christian officers, led by Major Gideon Orkar, attempt to overthrow Babangida in an unsuccessful coup. |
1992 | | Two political parties, the Social Democratic Party (SDP) and the National Republican Convention (NRC) were established by Babangida in an attempt to return to civilian rule. |
1993 | 12 June | Moshood Kashimawo Olawale Abiola won a presidential election. Babangida annulled the results. |
26 August | Babangida stepped down due to pressure from the Armed Forces Ruling Council. Ernest Adegunle Oladeinde Shonekan assumed power as Interim Head of State. |
17 November | Shonekan was forced to resign from office. Defence Minister Sani Abacha became Head of State and established the Provisional Ruling Council of Nigeria. |
1995 | 13 March | The Abacha administration arrested Obasanjo for allegedly supporting a secret coup plot. |
10 November | Human and environmental rights activist Ken Saro-Wiwa was hanged with eight others. |
1998 | 8 June | Abacha died from a heart attack. Abdusalami Abubakar became Head of State and Chairman of the Provisional Ruling Council of Nigeria and lifted the ban on political activity. |
15 June | Obasanjo was released from prison. |
1999 | 10 February | Obasanjo was elected President. |
29 May | Obasanjo was sworn in, ushering in the Fourth Republic. |
19 December | Obasanjo ordered the Nigerian Armed Forces to raid the town of Odi in the Niger Delta, in response to the murder of twelve policemen by local militia. |
2000 | 27 January | Sharia was established in the predominantly Muslim state of Zamfara. |
May | Religious riots erupted in Kaduna over the implementation of sharia. |
5 June | The Obasanjo administration established the Niger Delta Development Commission (NDDC) to tackle human and ecological issues in the Niger Delta region of Southern Nigeria. |