Regionalism was fully operated in Nigeria by the Richard Constitution. The Richard Constitution was introduced in 1946 during the British colonial rule of Nigeria. The Constitution created a federal system of government, which divided Nigeria into three regions: the Northern Region, the Western Region, and the Eastern Region. Each region had its own government and legislature, with significant powers over local affairs.
The introduction of regionalism was a significant departure from the previous system of centralized government, which had been in place before the Richard Constitution. Regionalism allowed for greater local control and autonomy, which was seen as a way to accommodate the diversity of Nigeria's ethnic groups and their different political aspirations.
Under the Richard Constitution, each region had its own constitution and a governor appointed by the British colonial government. However, the Constitution also included provisions that ensured the ultimate authority of the British colonial government over Nigeria. For example, the governor-general, appointed by the British monarch, had the power to veto any legislation passed by the regional governments.
In summary, regionalism was fully operated in Nigeria by the Richard Constitution, which created a federal system of government and divided Nigeria into three regions. While regionalism allowed for greater local control and autonomy, it also ensured the ultimate authority of the British colonial government over Nigeria.