Out of the nine member SMC, only Ironsi and the military governor of the East, Lt Col. Chukwuemeka Odumegwu Ojukwu were Igbo.

Source: https://hallmarknews.com/ironsi-nigerias-most-patriotic-nationalistic-leader-ever/

What we were made to understand was that they did not want Aguiyi Ironsi as Head of State.

Source: https://punchng.com/how-coupists-killed-my-father-as-governor-and-visiting-head-of-state-ironsi-donald-fajuyis-eldest-son/

When Obasanjo interpreted his friend’s request as a request for amnesty, Ironsi said it would be the responsibility of the Supreme Military Council to decide, when inaugurated.

Source: https://www.thenews-chronicle.com/did-general-aguiyi-ironsi-deserve-to-die-part-2/