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Independence and federal republic

Nigeria gained a degree of self-rule in 1954, and full independence from the United Kingdom on 1 October 1960, as the Federation of Nigeria with Abubakar Tafawa Balewa as its Prime Minister, while retaining the British monarch, Elizabeth II, as nominal head of state and Queen of Nigeria. Azikiwe replaced the colonial governor-general in November 1960. At independence, the cultural and political differences were sharp among Nigeria's dominant ethnic groups: the Hausa in the north, Igbo in the east and Yoruba in the west. The Westminster system of government was retained, and thus the President 's powers were generally ceremonial. The parliamentary system of government had Abubakar Tafawa Balewa as Prime Minister and Nnamdi Azikiwe as the ceremonial president. The founding government was a coalition of conservative parties: the Northern People's Congress led by Sir Ahmadu Bello, a party dominated by Muslim northerners, and the Igbo and Christian-dominated National Council of Nigeria and the Cameroons led by Nnamdi Azikiwe. The opposition consisted of the comparatively liberal Action Group, which was largely dominated by the Yoruba and led by Obafemi Awolowo. An imbalance was created in the polity as the result of the 1961 plebiscite. Southern Cameroons opted to join the Republic of Cameroon while Northern Cameroons chose to join Nigeria. The northern part of the country became larger than the southern part.