Derg in the context of "Somali Salvation Democratic Front"

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.

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.