The Derg or Dergue (Ge'ez: ደርግ, meaning "committee" or "council") is the short name of the Coordinating Committee of the Armed Forces, Police, and Territorial Army that ruled Ethiopia between 1974 to 1987. It took power following the ousting of Emperor Haile Selassie I. Soon after it was established, the committee was formally renamed the Provisional Military Administrative Council, but continued to be known popularly as "the Derg". In 1975, it embraced communism and remained in power until 1987, when it established the People's Democratic Republic of Ethiopia.
Between 1975 and 1987, the Derg executed and imprisoned tens of thousands of its opponents without trial.
Read more about Derg: Formation and Growth, Mengistu's Leadership, Ethiopian Civil War, Aid and Controversy, End of The Derg, Chairmen, PMAC Standing Committee (January 1985)