How did the federal military government divide Nigeria’s regions into states in 1967?

In May 1967, the federal military government of Nigeria, led by Yakubu Gowon, promulgated a decree that divided the country's four existing regions into 12 states.123

This administrative restructuring was a strategic attempt to break the political power of the regions, which had been dominated by specific ethnic groups. The new state configuration included six states in the north and three in the east. This move occurred simultaneously with the Eastern region's authorization for Odumegwu Ojukwu to establish a sovereign republic, a development that ultimately led to the Nigerian Civil War.123