Derg in the context of "Somali invasion of Ogaden"

The Ethiopian Empire, historically known as Abyssinia or simply Ethiopia, was a sovereign state that encompassed the present-day territories of Ethiopia and Eritrea. It existed from the establishment of the Solomonic dynasty by Yekuno Amlak around 1270 until the 1974 coup d'état by the Derg, which ended the reign of the final Emperor, Haile Selassie. In the late 19th century, under Emperor Menelik II, the empire expanded significantly to the south, and in 1952, Eritrea was federated under Selassie's rule. Despite being surrounded by hostile forces throughout much of its history, the empire maintained a kingdom centered on its ancient Christian heritage.

Founded in 1270 by Yekuno Amlak, who claimed to descend from the last Aksumite king and ultimately King Solomon and the Queen of Sheba, it replaced the Agaw kingdom of the Zagwe. While initially a rather small and politically unstable entity, the Empire managed to expand significantly under the crusades of Amda Seyon I (1314–1344) and Dawit I (1382–1413), temporarily becoming the dominant force in the Horn of Africa. The Ethiopian Empire would reach its peak during the long reign of Emperor Zara Yaqob (1434–1468). He consolidated the conquests of his predecessors, built numerous churches and monasteries, encouraged literature and art, centralized imperial authority by substituting regional warlords with administrative officials, and significantly expanded his hegemony over adjacent Islamic territories.

On 12 September 1974, Emperor Haile Selassie was deposed by the Coordinating Committee of the Armed Forces, Police, and Territorial Army, a military junta that consequently ruled Ethiopia as the Derg until 28 May 1991.

In February 1974, the Ethiopian Revolution was accompanied by mutinies of units of the Imperial Army, which were ignited over resentment of low payment. The Derg established the Coordinating Council of the Armed Forces in June 1974, and grew rapidly to topple the ministers of Haile Selassie under Prime Minister Endelkachew Makonnen. Upon deposing the emperor, many of his personages and Imperial family members fled to London like Crown Prince Asfaw Wossen. On 27 March 1975, the Derg officially abolished the monarchy and the Ethiopian Empire as a whole, and began implementing a Marxist-Leninist system, along with nationalizing all properties. Haile Selassie died on 27 August, with different sources attributing his death to strangulation by the order of the military government or natural causes during a prostate operation.

The Ogaden War, also known as the Ethio-Somali War (Somali: Dagaalkii Xoraynta Soomaali Galbeed, Amharic: የኢትዮጵያ ሶማሊያ ጦርነት, romanized: ye’ītiyop’iya somalīya t’orinet), was a military conflict between Somalia and Ethiopia fought from July 1977 to March 1978 over control of the sovereignty of the Ogaden region. Somalia launched an invasion in support of the Western Somali Liberation Front (WSLF) insurgency, triggering a broader inter-state war. The intervention drew the disapproval of the Soviet Union, which subsequently withdrew its support for Somalia and backed Ethiopia instead.

Ethiopia was saved from defeat and permanent loss of territory through a massive airlift of military supplies worth $1 billion, the arrival of more than 12,000 Cuban soldiers and airmen and 1,500 Soviet advisors, led by General Vasily Petrov. On 23 January 1978, Cuban armored brigades inflicted the worst losses the Somali forces had ever taken in a single action since the start of the war.

Somali Salvation Democratic Front (SSDF) (Somali: Jabhadda Diimuqraadiga Badbaadinta Soomaaliyeed), initially known as the Democratic Front for Salvation of Somalia, was a political and paramilitary umbrella organization in Somalia. Founded in 1978 by several army officers, it was the first of several opposition groups dedicated to ousting the authoritarian regime of Mohamed Siad Barre. With its power base mainly within the Majeerteen clan, SSDF played a significant role in the country's complex political landscape under the leadership of Abdullahi Yusuf during the late 1970s and 2000s.

In 1982, it participated in attempted invasion of Somalia aimed at regime change with the support of Ethiopia. The joint 1982 offensive backfired as it ultimately consolidated Barre’s control. Amnesty and financial incentives prompted the majority of SSDF fighters to surrender and rejoin the regime in 1983. The organization fragmented under government pressure.

The Somali National Army (Somali: Ciidanka Xooga Dalka Soomaaliyeed, lit. 'Somali Ground Forces') are the ground forces component of the Somali Armed Forces.

Since Somali independence in 1960, the Army fought to expand and increase Somalia's sphere of influence throughout the Horn of Africa counter to Ethiopia's and Kenya's ambitions, because of this, Somalia had amassed large ground forces. After the fall of Mohammed Siad Barre the Armed Forces began an unsteady rebirth in the 21st century.

The People's Democratic Republic of Ethiopia (PDRE; Amharic: የኢትዮጵያ ሕዝባዊ ዲሞክራሲያዊ ሪፐብሊክ, romanized: Ye-Ītyōṗṗyā Həzbāwī Dīmōkrāsīyāwī Rīpeblīk) was a socialist state that existed in Ethiopia and present-day Eritrea from 1987 to 1991.

The PDRE was established in February 1987 as a Marxist-Leninist one-party state upon the adoption of the 1987 Constitution, three weeks after its approval in the national referendum. The Derg, the military junta that had ruled Ethiopia as a provisional government since 1974, planned for transition to civilian rule and proclaimed a socialist republic in 1984 after five years of preparation. The Workers' Party of Ethiopia (WPE) was founded that same year as a vanguard party led by Derg chairman Mengistu Haile Mariam. The Derg was dissolved with the proclamation of the PDRE, but continued to rule de facto until September when the new government took office, three months after the June general election. It was dominated by surviving Derg members, with Mengistu as both President of Ethiopia and General Secretary of the WPE.

The Eritrean War of Independence was an armed conflict and insurgency aimed at achieving self-determination and independence for Eritrea from Ethiopian rule. Starting in 1961, Eritrean insurgents engaged in guerrilla warfare to liberate Eritrea Province from the control of the Ethiopian Empire under Haile Selassie and later the Derg under Mengistu. Their efforts ultimately succeeded in 1991 with the fall of the Derg regime.

Eritrea was an Italian colony from the 1880s until the Italians were defeated by the Allies in World War II in 1941. Afterward, Eritrea briefly became a British protectorate until 1951. The United Nations convened after the war to decide Eritrea's future, eventually voting in favor of a federation between Eritrea and Ethiopia. As a result, Eritrea became a constituent state of the Federation of Ethiopia and Eritrea. The federation was intended to last for ten years, during which Eritrea would have limited autonomy, such as its own parliament, while remaining under the Ethiopian crown. However, Eritrea's autonomy was curtailed and the region was effectively governed as a police state by imperial authorities during the 1950s. As popular dissatisfaction with Ethiopian rule grew, an independence movement emerged under the banner of the Eritrean Liberation Front (ELF) in 1961.

In political contexts, a cadre (/ˈkɑːdrə/, also UK: /ˈkɑːdər/, also US: /ˈkɑːdreɪ/) consists of persons who function as leaders within a political organization.In some socialist states, a cadre is a group of people trained to carry out the goals of the party-state and to disseminate and enforce official ideology. These groups aim to stimulate loyalty by mobilizing citizens and by encouraging ideological and policy consensus. Cadres can be deployed in the field or employed in central offices by a political party, by the state, or by the secret police. They are often formed in order to break apart existing class hierarchies among citizens of a party-state. Such cadres have operated in a number of different countries: for example in the Soviet Union (1922 to 1991) and in Ethiopia during the Derg (1974 to 1987). As of 2025 the People's Action Party and People's Republic of China maintains cadre systems.

Stuart Christopher Munro-Hay (21 April 1947 – 14 October 2004) was a British archaeologist, numismatist and Ethiopianist. He studied the culture and history of ancient Ethiopia, the Horn of Africa region and South Arabia, particularly their history of coins.

Born in Northern Ireland, he was initially called Stuart Christopher H. McIlwrath, but took his mother's maiden name after his parents separated. Munro-Hay studied Egyptology at the University of Liverpool from 1970 to 1974. As a student and collaborator of Neville Chittick, he worked on the 1973-74 excavation project of the British Institute in Eastern Africa (BIEA) in Aksum, the capital of the late-antique Aksumite Empire. The excavations had to be cancelled due to the Derg's coup d'état in 1974, but Munro-Hay continued to dedicate his work to researching the history of Aksum, and in particular compiled a large collection of Aksumite coins. He completed his doctorate in 1978 at the London School of Oriental and African Studies (SOAS), supervised by the then BIEA chairman Laurence Kirwan, his thesis was titled A Reappraisal of the History and Development of the Aksumite State from Numismatic and Archaeological Evidence.

The Ethiopian Revolution (Amharic: የኢትዮጵያ አብዮት) was a period of civil, police and military upheaval in Ethiopia to protest against the weakened Haile Selassie government. It is generally thought to have begun on 12 January 1974 when Ethiopian soldiers began a rebellion in Negele Borana, with the protests continuing into February 1974. People from different occupations, starting from junior army officers, students and teachers, and taxi drivers, joined a strike to demand human rights, social change, agrarian reforms, price controls, free schooling, and releasing political prisoners, and labor unions demanded a fixation of wages in accordance with price indexes, as well as pensions for workers, etc.

In June 1974, a group of army officers established the Coordinating Committee of the Armed Forces, later branding itself as the Derg, which struggled to topple Haile Selassie's cabinet under Prime Minister Endelkachew Makonnen. By September of that year, the Derg began detaining Endalkachew's closest advisors, dissolved the Crown Council and Imperial Court and disbanded the emperor's military staff. The Ethiopian Revolution ended with the 12 September coup d'état against Haile Selassie by the Coordinating Committee.

Amha Selassie (Ge'ez: አምሃ ሥላሴ, romanized: Āmiha Śəllase, lit. 'Salute of the Trinity'; born Asfaw Wossen Tafari; 27 July 1916 – 17 January 1997) was Emperor-in-exile of Ethiopia. As son of Haile Selassie, he was Crown Prince and was proclaimed monarch three times. He was first proclaimed Emperor during an unsuccessful coup attempt against his father in December 1960, during which he alleged that he was detained and compelled to accept the title. After his father was deposed in a later coup, he was proclaimed King (not Emperor) in absentia by the Derg on 12 September 1974 in an act which he never accepted as legitimate and that ended in the abolition of the Ethiopian monarchy on 21 March 1975. He was again proclaimed Emperor in exile on 8 April 1989. This time he sanctioned the proclamation and accepted its legitimacy. After his accession, his full reign name was His Imperial Majesty Emperor Amha Selassie I, Elect of God, Conquering Lion of the Tribe of Judah and King of Kings of Ethiopia.

The Workers' Party of Ethiopia (Amharic: የኢትዮጵያ ሠራተኞች ፓርቲ, romanized: Ye'Ityopia Serategnoch Parti, WPE) was a Marxist–Leninist communist party in Ethiopia from 1984 to 1991 led by General Secretary Mengistu Haile Mariam. The Workers' Party of Ethiopia was founded in 1984 by the Derg, the ruling provisional government of Ethiopia, as the vanguard party for a planned future socialist state. In 1987, the WPE became the ruling party after the establishment of the People's Democratic Republic of Ethiopia, and the only legal political party until it was disbanded in 1991. A party was attempted to be formed with the same name in August 2022, but the application was rejected.

Mengistu Haile Mariam (Amharic: መንግሥቱ ኀይለ ማርያም, pronunciation: [mənɡɨstu haɪlə marjam]; born 21 May 1937) is an Ethiopian former politician, revolutionary, and military officer who served as the head of state of Ethiopia from 1977 to 1991. He was General Secretary of the Workers' Party of Ethiopia from 1984 to 1991, chairman of the Derg—the Marxist–Leninist military junta that ruled Ethiopia—from 1977 to 1987, and president of the People's Democratic Republic of Ethiopia (PDRE) from 1987 to 1991.

The Derg seized power in the Ethiopian Revolution following the overthrow of Emperor Haile Selassie in 1974, marking the end of the Solomonic dynasty which had ruled Ethiopia since the 13th century. Mengistu purged his rivals within the Derg and made himself dictator of Ethiopia, attempting to modernize the feudal economy of Ethiopia through Marxist–Leninist-inspired policies such as nationalization and land redistribution. His bloody consolidation of power in 1977–1978 is known as the Ethiopian Red Terror—a brutal crackdown on opposition groups and civilians following a failed assassination attempt by the Ethiopian People's Revolutionary Party (EPRP) in September 1976, after it had ignored the Derg's invitation to join the union of socialist parties. The death toll is unknown but is estimated at between 30,000 and 750,000 by the Ethiopian Red Terror Documentation and Research Center.

General elections were held in Ethiopia on 14 June 1987 for seats in its Shengo. This was the first election since Emperor Haile Selassie was deposed in the Ethiopian Revolution as well as the first–and as it turned out, only–election under the 1987 constitution, which replaced the Derg regime with the People's Democratic Republic of Ethiopia (PDRE).

This is a list of presidents of Ethiopia, and also a list of heads of state after the fall of the Ethiopian Empire in 1974.

Until the Ethiopian Revolution of 1974, the heads of state of Ethiopia were either emperors or regents. From the coup d'état of the Derg leading to the fall of the empire in September 1974 until March 1975, the Derg considered the crown prince Asfaw Wossen (later regnal name Amha Selassie) as the king (not emperor) and the nominal head of state – which the crown prince refused to accept. During this time, the chairmen of the Derg, the leaders of the Derg, were to be considered as acting heads of state. On 21 March 1975, the Derg military junta abolished the monarchy and fully took over. Until the establishment of the People's Democratic Republic of Ethiopia in 1987, still dominated by Derg figures, chairmen of the Derg have to be considered heads of state – but not presidents. After the fall of the Derg and the establishment of the Transitional Government of Ethiopia in 1991, the first immediate president (Meles Zenawi) has to be considered an Interim President.