The conflict, which erupted shortly after the end of World War II, consisted of a Communist-led uprising against the established government of the Kingdom of Greece.

The struggle was the first proxy conflict of the Cold War and represents the first example of postwar involvement on the part of the Allies in the internal affairs of a foreign country,[13] an implementation of the containment policy suggested by US diplomat George F. Kennan in his Long Telegram of February 1946.

The Organization for the Protection of the People's Struggle (OPLA) was founded as EAM's security militia, operating mainly in the occupied cities and most particularly Athens.

The Greek landscape was favourable to guerrilla operations, and by 1943, the Axis forces and their collaborators were in control only of the main towns and connecting roads, leaving the mountainous countryside to the resistance.

[citation needed] EAM-ELAS in particular controlled most of the country's mountainous interior, while EDES was limited to Epirus and EKKA to eastern Central Greece.

[citation needed] Ioannis Rallis, the Prime Minister of the collaborationist government sought to combat the rising influence of the EAM, and was fearful of an eventual takeover after the German defeat.

As the end of the war approached, the British Foreign Office, fearing a possible Communist upsurge, observed with displeasure the transformation of ELAS into a large-scale conventional army more and more out of Allied control.

[18] After the declaration of the formation of the Security Battalions, KKE and EAM implemented a pre-emptive policy of terror, mainly in the Peloponnese countryside areas close to garrisoned German units, intending to ensure civilian allegiance.

[20] In March 1944, EAM established the Political Committee of National Liberation (Politiki Epitropi Ethnikis Apeleftherosis, or PEEA), in effect a third Greek government to rival those in Athens and Cairo.

Advised by British ambassador Reginald Leeper, Papandreou demanded the disarmament of all armed forces apart from the Sacred Band and the III Mountain Brigade and the constitution of a National Guard under government control.

The Communists, believing that it would leave the ELAS defenseless against its opponents, submitted an alternative plan of total and simultaneous disarmament, but Papandreou rejected it, causing EAM ministers to resign from the government on December 2.

On 1 December 1944, the Greek "National Unity" government of Papandreou announced an ultimatum for the general disarmament by 10 December of all guerrilla forces, excluding the tactical forces (the III Greek Mountain Brigade and the Sacred Band);[24] and also a part of EDES and ELAS that would be used, if it was necessary, in Allied operations in Crete and Dodecanese against the remaining German Army units.

This signaled the beginning of the Dekemvriana (Greek: Δεκεμβριανά, "the December events"), a 37-day period of full-scale fighting in Athens between EAM fighters and smaller parts of ELAS and the forces of the British army and the government.

The British, alarmed by the initial successes of EAM-ELAS and outnumbered, flew in the 4th Indian Infantry Division from Italy as emergency reinforcements.

It provided for the complete demobilisation of the ELAS and all other paramilitary groups, amnesty for only political offenses, a referendum on the monarchy and a general election to be held as soon as possible.

The KKE disavowed Velouchiotis when he called on the veteran guerrillas to start a second struggle; shortly afterwards, he committed suicide surrounded by security forces.

[29] The KKE boycotted the March 1946 elections, which were won by the monarchist United Alignment of Nationalists (Inomeni Parataxis Ethnikofronon), the main member of which was Konstantinos Tsaldaris's People's Party.

The change of political attitude and the choice to escalate the crisis derived primarily from the conclusion that regime subversion, which had not been successful in December 1944, could now be achieved.

Fighting resumed in March 1946, as a group of 30 ex-ELAS members attacked a police station in the village of Litochoro, killing the policemen, the night before the elections.

[30] The KKE kept an open line of communication with the Soviet Communist Party, and its leader, Nikos Zachariadis, had visited Moscow on more than one occasion.

When DSE partisans entered a village asking for supplies, citizens were supportive (in previous years, EAM could count on two million members across the whole country) or did not resist.

When government troops arrived at the same village, citizens who had supplied the partisans were immediately denounced as Communist sympathizers and usually imprisoned or exiled.

Among analysts emphasising the KKE's perceived control and guidance by foreign powers, such as the Soviet Union and Yugoslavia, some estimate that of the DSE's 20,000 fighters, 14,000 were Slavic Macedonians from Greek Macedonia.

[37] The alliance of the DSE with the Slavic Macedonians caused the official Greek state propaganda to call the Communist guerrillas Eamovulgari (from EAM plus Bulgarians).

Supporters emphasise instead the DSE's conduct of a war effort across the country aimed at "a free and liberated Greece from all protectors that will have all the nationalities working under one Socialist State".

Advisers, funds, and equipment were now flooding into the country from Western Allies, and under their guidance the Greek army launched a series of major offensives into the mountains of central Greece.

After a year of increasing acrimony, Tito closed the Yugoslav border to the DSE in July 1949, and disbanded its camps inside Yugoslavia.

To terrify urban areas assisting DSE's III Division, the forces decapitated a number of dead fighters and placed them in central squares.

On April 21, 1967, a group of rightist and anti-communist army officers executed a coup d'état and seized power from the government, using the political instability and tension of the time as a pretext.

After the collapse of the military junta, a conservative government under Konstantinos Karamanlis led to the abolition of monarchy, the legalization of the KKE, and a new constitution, which guaranteed political freedoms, individual rights, and free elections.