President of Ethiopia (1987–91). An army officer, Mengistu first came to prominence in 1974, when the army staged a successful coup against the regime of Emperor Haile Selassie. Appointed acting chairman of the provisional army council, he became head of state in a second coup in 1977. With aid from the Soviet Union and Cuba, he made Ethiopia into a Marxist–Leninist republic, ruthlessly suppressing all opposition. He imposed agricultural collectivization and mass deportations. He pursued the war against the breakaway province of Eritrea, building his forces into the largest army in Africa. In 1984–85 his policies exacerbated one of the worst periods of famine and drought to affect the Horn of Africa, during which many thousands of Ethiopians died. In 1987 Mengistu introduced civilian rule; having banned all but his Workers’ Party, he took the Presidency unopposed. After surviving one attempted coup in 1989, his downfall and exile came in May 1991, when a coalition of resistance movements from Eritrea and Tigray, which had made steady advances since the mid-1980s, overran Addis Ababa. In 1995 Mengistu was found guilty in absentia of genocide in his native country.