There were not many military leaders who were Generals in the Army before they became heads of states in Nigeria. Some were Colonels, Brigadier Generals, and only a sparse number were Major- Generals.
Before going any further, it is necessary to be acquainted with senior ranks in the Nigerian army. Starting from the lowest, they are: 2nd Lieutenant, Lieutenant, Captain, Major, Lieutenant Colonel, Brigadier General, Major General, Lieutenant General, and General.
During the Military regime in Nigeria, there were a total number of eight heads of state. They include: Aguiyi Ironsi, Yakubu Gowon, Murtala Mohammed, Olusegun Obasanjo, Muhammadu Buhari, Ibrahim Babangida, Sani Abacha and Abubakar Abdusalam.
Listed below are the past Heads of states in Nigeria and their military ranks:
1. Major General Johnson Aguiyi Ironsi:
Johnson Aguiyi Ironsi joined the Nigerian regiment in 1842 as a private with the seventh battalion. In 1965, he rose to the rank of a Major General.
He became the military head of state in January 1966 and was killed during a coup in July that same year.
2. Lieutenant Colonel Yakubu Gowon:
Yakubu Gowon was commissioned as a second Lieutenant in the Army on the 19th October 1955, his 21st birthday. He became a Lieutenant Colonel in 1966 before he became the head of state. However, by virtue of his political post, he was promoted later to the rank of General.
3. Brigadier General Murtala Mohammed:
Murtala Mohammed was promoted to the rank of Brigadier General in October 1971. He was a part of the coup that brought in Yakubu Gowon, and although he wanted to occupy the post at that time, he was a junior.
He became the head of state in 1975, until his assassination in 1976.
4. Major General Olusegun Obasanjo:
Olusegun Obasanjo enlisted in the Nigerian Army in March 1958 due to his family’s inability to send him to the university. He served as head of state in Nigeria from 1976 to 1979 before relinquishing power to civilian government.
5. Major General Muhammadu Buhari:
In 1963, at age 20 he was commissioned a second lieutenant and appointed platoon commander of the second infantry battalion. He later became head of state in 1983.
6. Major General Ibrahim Babangida:
During the regime of Muhammadu Buhari, Babangida became a Major General in the army. He later became head of state in 1985 until his resignation in 1993.
7. General Sani Abacha:
Sani Abacha served as military head of state from 1993 until his death in 1998. According to Wikipedia, in 1993, he became the first Nigerian Army officer to attain the rank of a full military General without skipping a single rank.
8. General Abdusalaami Abubakar:
He was initially in the Nigerian Air force before joining the Nigerian Army. He became head of state a day after the death of Sani Abacha in 1998.