Nigeria's Biafran war 1967-1970, a conflict between the Muslim Hausa and the Christian Igbo. Causes: British Colonialism, ethno-religious violence, anti-Igbo pogroms in Northern Nigeria, military coups, persecution of Igbo, control over oil production in the Niger Delta. Massacres prompted thousands of Igbos to flee east where their people were the dominant ethnic group. In 1967 the State of Biafra was declared. When it lost its oil fields, the main source of revenue, without funds to import food, one million of its citizens died of severe malnutrition. The Eastern region which had seceded as a state was defeated.