The Derg (Ge'ez: ደርግ) or Dergue was a military junta that ruled Ethiopia between 1974 to 1987, taking power following the ousting of Haile Selassie I. Derg, which means "committee" or "council" in Ge'ez, is the short name of the Coordinating Committee of the Armed Forces, Police, and Territorial Army. The committee was formally renamed the Provisional Military Administrative Council later in 1974, but was still popularly known as the Derg. The Derg embraced Communism in 1975, and its regime eventually became formally known as the Provisional Military Government of Socialist Ethiopia.

Between 1975 and 1987, the Derg executed and imprisoned tens of thousands of its opponents without trial.

The Coordinating Committee of the Armed Forces, Police, and Territorial Army, or the Derg (Ge'ez "Committee"), was officially announced 28 June 1974 by a group of military officers to maintain law and order due to the powerlessness of the civilian government following widespread mutiny in the armed forces of Ethiopia earlier that year. Its members were not directly involved in those mutinies (as far as anyone presently knows), nor was this the first military committee organized to support the administration of Prime Minister Endelkachew Makonnen: Alem Zewde Tessema had established the Armed Forces Coordinated Committee 23 March. However, over the following months radicals in the Ethiopian military came to believe he was acting on behalf of the hated aristocracy, and when a group of notables petitioned for the release of a number of government ministers and officials who were under arrest for corruption and other crimes, three days later the Derg was announced.

Haile Selassie I (Ge'ez: ኃይለ፡ ሥላሴ, "Power of the Trinity") (23 July 1892 – 27 August 1975), born Tafari Makonnen, was Ethiopia's regent from 1916 to 1930 and Emperor of Ethiopia from 1930 to 1974. He was the heir to a dynasty that traced its origins to the 13th century, and from there by tradition back to King Solomon and Queen Makeda, Empress of Axum, known in the Abrahamic tradition as the Queen of Sheba. Haile Selassie is a defining figure in both Ethiopian and African history.

At the League of Nations in 1936, the emperor condemned the use of chemical weapons by Italy against his people. His internationalist views led to Ethiopia becoming a charter member of the United Nations, and his political thought and experience in promoting multilateralism and collective security have proved seminal and enduring. His suppression of rebellions among the nobles (mekwannint), as well as what some perceived to be Ethiopia's failure to modernize adequately, earned him criticism among some contemporaries and historians.

The Ethiopian Civil War began on November 28, 1974 when the Marxist Derg staged a coup d'état against Emperor Haile Selassie, and lasted until the Ethiopian People's Revolutionary Democratic Front (EPRDF), a coalition of rebel groups, overthrew the government in 1991. The war overlapped other Cold War conflicts in Africa, such as the Angolan Civil War (1975–2002). The war left between 230,000-1.4 million dead.

The revolutionaries abolished the monarchy in March 1975 and Crown Prince Asfaw Wossen settled permanently in London, England where several other members of the Imperial family were already based. The other members of the Imperial family who were still in Ethiopia at the time of the revolution were imprisoned, including Amha Selassie's father the Emperor, his daughter by his first marriage, Princess Ijigayehu, his sister Princess Tenagnework and many of his nephews, nieces, relatives and in-laws. In 1975, first his father Emperor Haile Selassie then in 1977, his daughter Princess Ijigayehu died in detention. Members of the Imperial family remained imprisoned until 1988 (for the women) and 1989 (for the men).