On April 21st, 1967, Athenians awoke to find that a coup d’état had left a military dictatorship in control of Greece. At the start of the 1960s, Greece was firmly in the hands of right-wing parties, which had run the country since 1946. After a bloody civil war put down a communist insurgency in 1949, Greek governments turned to authoritarian rule, supported by the country’s monarch.
The key figure was Prime Minister Konstantinos Karamanlis, prime minister of Greece for eight years. But after two decades of unopposed rule by the right, change came with the elections of February 1964. Moderate centrists led by George Papandreou, who would take over as prime minister, defeated Karamanlis’s party.This alarmed the country’s conservative groups. The military feared reforms that would challenge the considerable power it had accumulated.

The elections also troubled young King Constantine II. After struggling with the Papandreou government, he provoked its fall in July 1965, only a year into its term. Papandreou’s collapse produced a political stalemate and the king was forced to declare early national elections in May 1967. With Papandreou and the moderate left in the lead, conservative forces feared the election. The upper echelons of the military began planning a coup, some say with the assistance of King Constantine. But while the king and the heads of the armed forces bought time, second-tier officials led by Colonel Geòrgios Papadòpulos took over in what became known as the Colonels’ Coup. On the night between April 20th (twentieth) and 21st (twenty first), 1967, Papadopoulos’s men seized strategic points in Athens and arrested thousands in order to neutralize potential opposition.

At dawn on April 21st (twenty first), the colonels demanded that the king support the coup. Constantine hedged for hours, but by evening named a new prime minister, Konstantinos Kollias, a conservative with strong monarchist ties. The colonels immediately abolished free elections and voided the Greek constitution. They then imposed nationwide martial law. Months later, Constantine organized a counter-coup in response. When it failed, Constantine was forced into exile. Georgios Papadopoulos then proceeded to take power into his own hands. Papadopoulos and his Colonels ruled until 1974, when the regime fell after the Greeks suffered a stinging defeat in their battle with Turkish forces that had invaded northern Cyprus.