Constitution of Ethiopia there was three Prime ministers including the first Prime Minister Makonnen Endelkachew and the last Prime Minister Abebe Aregai who was assassinate during the failed 1960 Ethiopian coup d'état attempt. Following the assassination of Prime Minister Abebe Aregai, Imru Haile Selassie served as Acting Prime Minister for only three days. the chief law marker The 1955 Constitution of Ethiopia The revised 1955 constitution of Ethiopia put in effect in 1961 following the failed 1960 Ethiopian coup d'état attempt.The 1955 revised Constitution of Ethiopia attempted to take Ethiopia towards a Constitutional Monarchy system. Under the 1955 constitution the office of the Prime Minister and Chamber of Deputies was given autonomy and power. Although the Prime Minister and parliament's power was stronger on paper, in practice the Emperor of Ethiopia control a significant power and rule the country as de jure absolute ruler. The first prime minister under the 1955 Constitution of Ethiopia was Prime Minister Aklilu Habte-Wold and the last Prime Minister was Mikael Imru who was dismissed following the 1974 revolution which established Provisional Military Government (PMG). The Provisional Military Government (PMG) (1974–1987) In September 1974 the last emperor of Ethiopia Haile Selassie was overthrow by a military coup. The Military Administration abolished the Monarchies of Ethiopia and established Provisional Military Government of Socialist Ethiopia. Chairman of the Provisional Military Government of Socialist Ethiopia was head of the government. From 1974 until 1987 the office of the Prime Minister was not in use until the declaration of 1987 Constitution of Ethiopia which created People's Democratic Republic of Ethiopia. The People's Democratic Republic of Ethiopia (PDRE) (1987–1991) The Prime Minister office become in effect following the declaration of People's Democratic Republic of Ethiopia. The 1987 Constitution of Ethiopia name the Prime Minister as the head of government and the principal advisor to the President of the People's Republic. The Prime Minister also holds the highest rank in the civil service of the central government. The Prime Minister is formally approved by the National Shengo upon the nomination of the President. In practice, the Prime Minister is chosen within the Workers' Party of Ethiopia (WPE) through deliberations by incumbent WEP Politburo members and retired WEP Politburo Standing Committee members. The first Prime Minister of the People's Democratic Republic of Ethiopia was Prime Minister Fikre Selassie Wogderess who served from 1987 to 1989. The last Prime Minister was Tesfaye Dinka