How did Nigeria gain independence?

As a British colony, the country became a Federation in 1954 and increasing degreesof internal self government were introduced by the British until the country became fully independent in 1960. There were two military coups in 1966. then in 1967 the Eastern Region seceded setting up the Igbo state of Biafra and civil war broke out in which 1 Million died. the war lasted until 1970 when Biafra surrendered and returned to Nigeria which has remained independent since but with several military coups and continuing ethnic and regional tensions.