General Yakubu Gowon assumed power on 1 August 1966 in a coup that deposed General Johnson Aguiyi-Ironsi. In May 1967 he reorganized the four regions in twelve states, appointing a military governor for each state. Gowon was deposed in a coup on 29 July 1975, replaced by General Murtala Muhammed.
Here Are Some Names Of Military Governors Created By The Gowon Proclamation Of A New 12 States To Replace The Four Regions:
References
Military Governors in Nigeria during the Yakubu Gowon regime Wikipedia(Text) CC BY-SA