Johnson Aguiyi-Ironsi

Ironsi issued Decree No. 34 in 1966, abolishing Nigeria's federal system and replacing it with a unitary state. This move aimed to reduce regional tensions but was widely opposed, particularly in the north, and contributed to his downfall.

Ironsi became Nigeria's first military head of state in 1966 after leading a coup that overthrew the civilian government. He suspended the constitution and established a military regime, citing corruption and political instability.

Ironsi was assassinated in 1966 during a counter-coup led by northern military officers. He was killed in Ibadan along with his host, Lieutenant Colonel Fajuyi. The coup brought Yakubu Gowon to power and deepened ethnic tensions.