The major innovation of the Republican Constitution of 1963 was that

The major innovation of the Republican Constitution of 1963 was that it abolished the Governor-General's office as the representative of the Queen. This means that the new constitution established an independent Nigerian presidency, replacing the previous system where Nigeria was still under the control of the British Monarch. The constitution also established the executive Presidential system, in which the President is both the head of state and the head of the government. This system replaced the parliamentary system in which the Prime Minister was the head of government, and the Governor-General was the head of state.