The Apostasia heralded a prolonged period of political instability, which weakened the fragile post-civil war order, and ultimately led to the establishment of the military regime in April 1967.
However, this was a result of election fraud and of a wide scale repression of left wing and center sympathizers by the police, military and paramilitary forces loyal to ERE.
It is claimed that, as repayment of such a favorable treatment, Papandreou agreed to accept an increased role for the King in the running of the armed forces, which were traditionally conservative and fiercely anticommunist.
In the government formed after the 1964 election, the defense minister was Petros Garoufalias, a loyal friend of Papandreou and one of his financial backers.
Soon after Papandreou had been sworn in again as prime minister, in early 1964, King Paul died and his 24-year-old son succeeded him as Constantine II.
The Centre Union was a party hastily formed, in late 1961, by the fusion of various centrist factions, which had previously been bitterly bickering with each other.
To complicate matters even further, Papandreou, 76 years of age in 1964, was expected soon to have to cede his place to a new leader, and many aspired to this position, most of all the powerful and considerably younger Finance Minister, Konstantinos Mitsotakis.
The purpose of the secret organization was apparently to oppose actual or perceived right-wing domination of the Greek army through the IDEA secret organization, which was perceived as still being active, and to help its own members obtain favorable postings (hence the reference to "meritocracy" in the acronym since there was a perception that choice postings and promotions went to sympathizers of IDEA regardless of merits).
The political turmoil began from then on and arose from the fact that the King had already decided upon Papandreou's successor, Georgios Athanasiadis-Novas, who was waiting in an adjoining room during the meeting.
Constantine II next induced some of Papandreou's dissidents, led by Stephanos Stephanopoulos, to form a government of "King's men", which lasted until December 22, 1966, amid mounting strikes and protests.
It was replaced on 3 April 1967 by another interim government under Panagiotis Kanellopoulos, who was the active leader of ERE (National Radical Union) and was still supposed to organize a fair election.
There therefore existed a strong possibility that the Centre Union would be forced into an alliance with the socialist EDA (United Democratic Left).
The sense of a "Communist threat", along with putschist tendencies in some nationalist fractions of the Hellenic Armed Forces, led to a coup d'état on 21 April 1967 which established a military dictatorship, better known as the "Regime of the Colonels".