[2] The only Greek career officer to rise to the rank of Field Marshal, Papagos became the first Chief of the Hellenic National Defence General Staff from 1950 until his resignation the following year.

[3][4] His father was Major General Leonidas Papagos from the island of Syros, who occupied senior posts during his military career, including Director of Personnel at the War Ministry and aide-de-camp to the King.

Promoted to lieutenant in 1911, Papagos participated in the Balkan Wars of 1912–13 attached to the field headquarters of the Crown Prince, and from 1913, King Constantine.

[3] Papagos remained Minister of Military Affairs until Kondylis' resignation on 30 November,[5] and was re-appointed to the post in the succeeding Konstantinos Demertzis cabinet on 13 December 1935 until 5 March 1936.

At the outbreak of the Greco-Italian War on 28 October 1940, he became Commander-in-Chief of the Army, a post he retained until the capitulation of the Greek armed forces following the German invasion of Greece in April 1941.

[10][11][12][13] He remained retired and held no active military position, but served as grand chamberlain to King Paul and in July 1947 was promoted to the exceptionally rare rank of full general as a token of honour.

[3] Papagos led the final victory of the government forces over the Communist Democratic Army of Greece, employing extensive American material aid (including napalm equipped aircraft [1][usurped]), and the extensive deployment of Hellenic Mountain Raider Companies of Special Forces (LOK), during the Grammos-Vitsi campaign between February and October of that year.

The British officer Christopher Woodhouse, who had been active in the Greek Resistance and knew the country well, considered that his predecessor, Lt. General Dimitrios Giatzis, had "virtually won the war" before his dismissal, but that Papagos' appointment was beneficial because Papagos, through his seniority and prestige, "could impose his own plans and wishes on both the Greek high command and the allied military missions, which had been for some months at loggerheads with each other.

[3] He continued to serve in his capacity as Commander-in-Chief until 1951,[3] while Greece was in a state of political instability, with splinter parties and weak politicians unable to provide a firm government.

For a time, the Palace feared that he might establish a dictatorship, largely due to his popularity, his image as a strong and determined leader, and the communist defeat in the civil war, which was attributed in great part to his leadership.

Despite his victory, Papagos was unable to form a government on this majority, and had to wait until the November 1952 elections, where his party tallied an impressive 49 percent of the popular vote, gaining 239 out of 300 seats in Parliament.

Though reluctant to confront Great Britain, demonstrations in the streets of Athens prompted him to order Greece's UN representative to raise the issue of Cyprus before the UN General Assembly in August 1954.

When the EOKA campaign to expel the British and initiate Enosis in Cyprus began in 1955, Papagos was in declining health and unwilling to act.

[citation needed] In January 1955, Papagos began to develop gastric issues, a result of his imprisonment during World War II; he appointed Stefanos Stefanopoulos to serve as provisional premier during his illness.