Major crises that led to the Nigerian Civil war:
(i) Tribal domination which was the culmination of the January 15 1966 first ever military coup in the country was a remote cause the Nigerian civil war. The coup was alleged to have been staged and led by the lgbo group because the politicians and the army officers killed did not include the Igbo. There was a counter coup staged by the Northern soldiers on July 29 1966 to counter the January 15 coup. General Ironsi was killed and Colonel Yakubu Gowon took over the mantle of leadership.
(ii) Another remote cause of the civil war was the Western Nigerian election rigging of 1965. The crisis was one of the factors that brought to an end the First Republic. The election crisis brought about a break down of law and order in the region and acted as an impetus to the military take-over of power in 1966 and the eventual civil war that followed in 1967.
(iii) Another cause was the accusation levelled against General Ironsi, for not dealing with the January 15 1966 coup plotters. The coup was viewed as tribal by some who felt that Ironsi should have punished the five army officers implicated in the coup. Those killed in the coup include; the Prime Minister, sir Abubakar Tafawa Balewa, Finance Minister, Chief Festus Okotie Eboh, the Premier of Northern Region and Sardauna of Sokoto, Sir Ahmadu Bello and Chief S.L. Akintola, the Premier of Western region. No igbo man was killed in the coup.
(iv)The introduction of a unitary system of government in place of a federal system by General Ironsi was seen as one of the remote causes of the civil war. Decree No 34 of 1966 which abolished a federal system, was viewed by some as a way of concentrating power in the hands of his own tribe. He was accused of promoting 21 army officers, 19 of whom were Igbo.
(v) Politicians of the First Republic were accused of politicising the army and in the area of promotion of men in the armed forces, those from their ethnic groups were first considered. Ethnicity played a major role in the affairs of the military, making it a necessary factor in the civil war of 1967. This is because ethnic sentiments played a major role in the take-over of power.
(vi) Another cause of the civil war was the over-ambition of some military officers who wanted to taste power at all costs.
(vii) Another remote cause of the civil war was the federal government accusing the Eastern Regional government of trying to control the oil fields in that area of the country when exploration or discovery of oil is the sole responsibility of the federal government.
(viii)The personality clash between Gowon and Ojukwu was also seen as one of the immediate causes of the civil war. At the exit of General Ironsi from office, the next senior officer was Brigadier Ogundipe and he was supposed to become the next Head of State. Instead of him, it was Colonel Gowon who was made the Head of State. Ojukwu protested this and was not happy with the development. Gowon was not his senior and so he was not ready to take orders from him.
(ix) Both military officers Ojukwu and Gowon felt that war was the last resort for agreement. This issue was seen as one of the immediate causes of the civil war.
(x) Gowon's administration created 12 states out of the existing four regions on May 27, 1967. This action which (played a crucial role in causing the civil war led to Ojukwu seceding Eastern Nigeria from the rest of the country on May 30 1967 and it eventually led to the civil war that started on July 6, 1967.
(xii) The killing of non-Igbos during the January 15 1966 coup in the country was seen as the major cause of the massacre of the Igbos in the Northern part of the country in September 1966. The result of this massacre was the recalling of all Easterners in all parts of the country by Lt. Colonel Ojukwu and at the same time expelling non-Easterners living in Eastern region. It was alleged that this massacre led to the eventual secession of the region and the civil war.
(xii) The Aburi meeting held at the instance of General Ankrah, Head of State of Ghana was another immediate cause of the Nigerian civil war. The agreement reached between Gowon and Ojukwu at this meeting was not respected by General Gowon. He was advised not to honour his own side of the agreement. This agreement would have made the regions stronger than the central government. However, this paved the way for the 1967 civil war that killed millions of Nigerians.