Jabarkan First Premiership dari Konstantinos Karamanlis

After World War II, Karamanlis quickly rose through the ranks of Greek politics. His rise was strongly supported by fellow party-member and close friend Lambros Eftaxias who served as Minister for Agriculture under the premiership of Konstantinos Tsaldaris. Karamanlis's first cabinet position was Minister for Employment in 1947 under the same administration. Karamanlis eventually became Minister of Public Works in the Greek Rally administration under Prime Minister Alexandros Papagos. He won the admiration of the US Embassy for the efficiency with which he built road infrastructure and administered American aid programs.

When Alexandros Papagos died after a brief illness (1955), King Paul of Greece appointed the 48-year-old Karamanlis as Prime Minister. The King did so, thus bypassing Stephanos Stephanopoulos and Panagiotis Kanellopoulos, the two senior Greek Rally politicians who were widely considered as the heavyweights most likely to succeed Papagos. Karamanlis first became prime minister in 1955, and reorganized the Greek Rally as the National Radical Union. One of the first bills he promoted as Prime Minister, implemented the extension of full voting rights to women, which stood dormant although nominally approved in 1952. Karamanlis won three successive elections (1956, 1958 and 1961).

In 1959 he announced a five-year plan (1960–64) for the Greek economy, emphasizing improvement of agricultural and industrial production, heavy investment on infrastructure and the promotion of tourism. On the international front, Karamanlis abandoned the government's previous strategic goal for enosis (the unification of Greece and Cyprus) in favour of independence for Cyprus. In 1958, his government engaged in negotiations with the United Kingdom and Turkey, which culminated in the Zurich Agreement as a basis for a deal on the independence of Cyprus. In 1959 the plan was ratified in London by Makarios III.