Also known as the Biafra war, Nigeria's civil war was one of the most divisive conflicts in post-independence Africa.

The war broke out in May 1967 when Chukwuemeka Odumegwu Ojukwu, the military governor of Nigeria's eastern region, declared the independence of the Republic of Biafra from Nigeria. The decision to break away stemmed from tensions between the Igbo ethnic group in the east and the Hausa group in the north. Reconciliation talks were unsuccessful and Ojukwu and his followers broke away following violence against Igbos living in the north.

The breakaway republic comprised of 9 states in Nigeria's eastern region. The declaration of independence led to a civil war between the region and the rest of Nigeria, who opposed secession.

An estimated 1-3 million people were killed during the 30-month long war. The conflict ended in January 1970 when Ojukwu fled the country, and Nigeria reabsorbed Biafra with a 'no victor, no vanquished' policy.

Lt. Col. Odumegwu Ojukwu, left, takes the oath of office shortly after a declaration of independence and the formation of the new state of Biafra on June 10, 1967.
Lt. Col. Odumegwu Ojukwu, left, takes the oath of office shortly after a declaration of independence and the formation of the new state of Biafra on June 10, 1967.
AP Photo
Nigerian troops enter Port Harcourt after taking it from Biafrian forces in 1968.
Nigerian troops enter Port Harcourt after taking it from Biafrian forces in 1968.
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A Nigerian artillery unit in Port Harcourt on May 19, 1968.
A Nigerian artillery unit in Port Harcourt on May 19, 1968.
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Lt Col. Ojukwu inspects Biafran troops on June 11, 1968.
Lt Col. Ojukwu inspects Biafran troops on June 11, 1968.
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A Biafran soldier carries an elderly woman from the wreckage of her home following an artillery bombardment by the Nigerian army in June 1968.
A Biafran soldier carries an elderly woman from the wreckage of her home following an artillery bombardment by the Nigerian army in June 1968.
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Young Biafran soldiers inspect an unexploded shell in June 1968.
Young Biafran soldiers inspect an unexploded shell in June 1968.
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Biafran soldiers advance towards a Nigerian army position in June 1968.
Biafran soldiers advance towards a Nigerian army position in June 1968.
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Wounded Biafran soldiers are transported across a river in June 1968.
Wounded Biafran soldiers are transported across a river in June 1968.
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Jubilant Biafran soldiers celebrate on top of a destroyed Nigerian army armored personnel carrier.
Jubilant Biafran soldiers celebrate on top of a destroyed Nigerian army armored personnel carrier.
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A soldier in the ruins of the Onitsha market after it was gutted during fighting in the city on July 16, 1968.
A soldier in the ruins of the Onitsha market after it was gutted during fighting in the city on July 16, 1968.
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Refugees flee the fighting in July 1968. Estimates of the number of dead from fighting, disease and starvation during the 30-month civil war are estimated at between <a href="index.php?page=&url=https%3A%2F%2Fwww.cnn.com%2F2020%2F01%2F15%2Fafrica%2Fbiafra-nigeria-civil-war%2Findex.html" target="_blank">1 and 3 million</a>.
Refugees flee the fighting in July 1968. Estimates of the number of dead from fighting, disease and starvation during the 30-month civil war are estimated at between 1 and 3 million.
Kurt Strumpf/Associated Press
Chief Anthony Enahoro, right, head of the Nigerian delegation, at the opening session of the Nigerian-Biafra peace talks in Addis Ababa, Ethiopia, on August 6, 1968. The talks were largely unsuccessful in curbing the conflict between Biafra and Nigeria.
Chief Anthony Enahoro, right, head of the Nigerian delegation, at the opening session of the Nigerian-Biafra peace talks in Addis Ababa, Ethiopia, on August 6, 1968. The talks were largely unsuccessful in curbing the conflict between Biafra and Nigeria.
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Nigerian police push back crowds of demonstrators outside the French Embassy in Lagos on September 16, 1968. An estimated 2,000 demonstrators presented the French ambassador with a letter protesting French assistance to Biafra. France provided weapons and mercenary fighters to Biafra and promoted their cause internationally, describing the situation as a genocide. <br />
Nigerian police push back crowds of demonstrators outside the French Embassy in Lagos on September 16, 1968. An estimated 2,000 demonstrators presented the French ambassador with a letter protesting French assistance to Biafra. France provided weapons and mercenary fighters to Biafra and promoted their cause internationally, describing the situation as a genocide.
Dennis Lee Royle/AP
People search the rubble following a bombing raid in Owerri in 1969.
People search the rubble following a bombing raid in Owerri in 1969.
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A group of emaciated children photographed in 1970. During the war, the Biafran government reported that Nigeria was using hunger as a weapon to win, and sought aid from the outside world. Nigeria led multiple<a href="index.php?page=&url=https%3A%2F%2Fedition.cnn.com%2F2020%2F01%2F15%2Fafrica%2Fbiafra-nigeria-civil-war%2Findex.html" target="_blank"> blockades preventing relief materials</a> from getting into Biafra. As a result, thousands of people starved. <br />
A group of emaciated children photographed in 1970. During the war, the Biafran government reported that Nigeria was using hunger as a weapon to win, and sought aid from the outside world. Nigeria led multiple blockades preventing relief materials from getting into Biafra. As a result, thousands of people starved.
Romano Cagnoni/Hulton Archive/Getty Images
Nigerians in the capital city of Lagos cheer the surrender of the Biafran forces on January 12, 1970. Nigerian leader Maj. Gen. Yakubu Gowon accepted the Biafran surrender and asked all Nigerians to greet the former rebels as brothers.
Nigerians in the capital city of Lagos cheer the surrender of the Biafran forces on January 12, 1970. Nigerian leader Maj. Gen. Yakubu Gowon accepted the Biafran surrender and asked all Nigerians to greet the former rebels as brothers.
Dennis Lee Royle/AP
Nigerians in Lagos react to news of the Biafrian surrender following the announcement of a ceasefire on January 12, 1970.
Nigerians in Lagos react to news of the Biafrian surrender following the announcement of a ceasefire on January 12, 1970.
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Gen. Yakubu Gowon, right, welcomes UN Secretary-General U Thant, left, as he arrives in Lagos to hold talks about the refugee crisis in the aftermath of the Biafran conflict on January 19, 1970.
Gen. Yakubu Gowon, right, welcomes UN Secretary-General U Thant, left, as he arrives in Lagos to hold talks about the refugee crisis in the aftermath of the Biafran conflict on January 19, 1970.
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