The Communist Party, due to its ideology, tried to connect with the working masses, mainly in the urban centers of Athens, Piraeus, Thessaloniki, Volos, and Kavala. In these areas, the Party's discourse during the 1920s had generally little resonance, confined mainly to poor working-class districts and a circle of young intellectuals. All the higher leading party bodies were staffed by communists who came from the Greek diaspora and whose main ideological influence had been the Second International. Therefore, in that decade, the central concern of the Executive Committee of the Comintern was for the KKE to acquire the characteristics and functions of a Bolshevik party. In the semi-urban and rural areas, the KKE's political discourse had a very limited reach, as it was nullified by the then-ongoing struggle between the followers of Venizelos and the pro-royalists.

This whole situation changed radically during the Axis Occupation, when the KKE, under the guise of anti-fascist resistance, began to develop aspirations of seizing power after a future liberation of Greece. When the Italian army invaded Greece in 1940, the leader of the KKE, Nikos Zachariadis, supported the national conscription undertaken by the dictator Ioannis Metaxas, who some days earlier had rejected the Italian ultimatum towards the Greek government. Zachariadis did so via letter, sent from the prisons of Corfu. It was the position of a  Communist leader operating outside the Comintern line, since in October 1940 Nazi Germany and the Soviet Union were effectively allies, having dismembered Poland a year earlier. Not surprisingly, then,  two more letters from  Zachariadis followed which argued that the war was merely a settlement of accounts between the capitalist powers, this time following the Comintern directive.

But when German troops invaded the Soviet Union on June 22, 1941, the KKE, like all communist parties, mobilized to resist the occupier. On September 27, 1941, the National Liberation Front (EAM) was founded, a front organization that had as its core KKE executives operating underground. The National People's Liberation Army (ELAS) followed a little time later, a military organization that very quickly equipped itself with the help of the Middle East Allied Headquarters and began to occupy mountainous rural areas, supplanting other resistance organizations. Additionally, by the middle of 1943, the Organization for the Protection of People's Fighters (OPLA) became active in major urban centers. Its objective was the physical elimination of all opponents of the KKE and was guided directly by the party's Political Bureau. Another power apparatus of the communists was the Militia and the Garrison, which controlled the districts of the urban centers and the mountainous and semi-mountainous regions of Greece. Therefore, by the end of 1943, the KKE controlled a large part of the Greek countryside, having also confiscated most of the armaments of the Italian occupation forces following Italy's capitulation in September 1943. At the time, this area was called "Free Greece". The occupying Wehrmacht could not fill the gap left by the Italians outside the urban centers.

In the areas where the KKE exercised power through ELAS, its sole weapon was violence or the threat of violence. The villagers, almost all uneducated, did not understand Marxism and liberalism, and therefore, the political propaganda of the party could not bear any fruit. Compulsory taxation of agricultural produce had been imposed under penalty of death, and all local authorities were under the suffocating control of party officials. In the Peloponnese, where the influence of the KKE had always been insignificant on account of the region being traditionally conservative, the violence used was unprecedented: executions, torture, and concentration camps for dissidents, men and women alike. Rural warehouses, schools, and monasteries were all used as concentration camps where dissidents were executed after torture. The same regime prevailed in almost all of Greece, except for the region of Epirus (where the anti-communist organization EDES dominated) the region of Eastern Macedonia (where the group of the Pontian chieftain Çauş Anton (Antonis Fosteridis) was active),  and Crete (where the strong Venizelist tradition left no political room for the communists). In total, EAM and ELAS controlled more than half of the Greek territory throughout 1944. At that time, there were three cores of power in Greek politics: the collaborationist government in Athens, the Allied-recognized Greek government-in-exile in Cairo, and the "mountain government" controlled by the KKE.

During this period, the KKE was cut off from the Comintern networks. Its main contact with the international communist movement was the Yugoslav leader Josip Tito. There was a permanent representative of the KKE at the Yugoslav communists’ headquarters, and the two organizations were undertaking joint actions in Northern Greece. Though the Yugoslav communists insisted in the summer of 1943 for the two parties to establish a common Balkan headquarters, the KKE rejected this proposal for two reasons. Firstly, it was afraid of Tito's hegemony and his ambitions in Macedonia. Secondly, it was the English, and not the Yugoslavs, that were funding the KKE.

Because of the uniform way in which the KKE used violence in the areas it controlled, we can claim with certainty that this violence was not spontaneous, but well-organized and centrally planned. After all, terrorism was, for the Bolsheviks, the model of every interwar communist party, an acceptable weapon for their domination. In the power struggle, the communists had no boundaries. Greece was no exception, and the weapons the party acquired during the period of the Axis Occupation gave it an opportunity it could not afford to miss. It is reasonable to assume that if the Second World War had not broken out, the KKE would have remained a marginal party representing 4-5% of the population.

Meanwhile, the closer the Axis defeat approached, the more the question of the Greek post-war regime became crucial to everyone concerned. The KKE wanted to keep all developments under its absolute control, that is, under the absolute control of ELAS bayonets. Reacting to this situation, the collaborationist government established the Security Battalions, an armed body equipped by the Germans and initially aimed at a two-front struggle against the monarchy and the communists. The Security Battalions comprised soldiers and officers who had previously faced persecution at the hands of the communists due to their political views. During the interwar period, most of them belonged to the Venizelist faction and had been ousted by the royalist government. They were not inherently pro-fascist, which can be confirmed by the fact that the power of the Security Battalions was growing while it was obvious that the Germans were going to lose the war. There were, on the other hand, some pro-Nazi military formations in Northern Greece, such as the groups of Poulos, Dagoulas, and Vichos.

The establishment of the Security Battalions, in addition to the protection it offered to the villagers from ELAS persecution, was also aimed towards a post-occupation regime. Understanding this, when the Germans withdrew in September 1944 from the Peloponnese, where the bulk of the Security Battalions were located, ELAS launched a major attack to exterminate them. Within forty days, about 1750 men of the Security Battalions and another 5,000 civilian villagers who followed them were brutally murdered. A similarly extensive massacre took place in the city of Kilkis, in Northern Greece, during the first week of November 1944, when 7,000 anti-communist armed and unarmed civilians were murdered in cold blood.

But the biggest crimes were committed in Athens in December 1944, during the so-called Dekemvriana, when the KKE attempted to seize power in the capital by force. The fighting in Athens lasted 33 days and resulted in the crushing of the communists after the intervention of 40,000 British soldiers. During the fighting, OPLA and the Militia, based on lists drawn up by the local KKE organizations, arrested dissidents and executed them in cold blood. After the ELAS defeat, dozens of mass graves were discovered in the districts of Athens. Still,  as they retreated from Attica, the communists took with them some 12,500 hostages on a deadly march through the snow. Approximately 1000 of them were either executed or died from the hardships. In Thessaloniki too, 1250 dissidents were transported on foot to a village outside the city, Agios Athanasios, where 600 were murdered by ELAS forces, while the rest were released in March 1945 after the Varkiza agreement (February 12, 1945). With this agreement, the defeated KKE was obliged to hand over the weapons of ELAS. But as it turned out, it did not remain faithful to the agreement and hid its best weaponry until, soon afterward, it would use it again in the civil war.

After the defeat of ELAS in the Battle of Athens, this red terrorism caused a wave of mass retaliation throughout Greece. Victims who escaped or relatives of those killed by the communist armed groups took the law into their own hands and started killing and abusing KKE officials who had not managed to hide in the mountains. Anti-communist groups were formed that hunted them, and if they didn't find them, they took revenge upon their relatives. The family responsibility that the communists had established was now turning against them. From March 1945 to the beginning of 1946, approximately 1300 leftists were murdered by anti-communist groups throughout Greece. In the meantime, the KKE made sure that communist executives (and thus potential targets for the anti-communist groups) could seek refuge in Bulkes (today Maglić, Serbia), a village in the northeast of Yugoslavia. About 4,000 other persecuted leftist rebels, who would form the core of the Democratic Army of Greece in the civil war that followed (1946-1949), took refuge in the mountains.

Nemesis was the deity of Greek mythology that represented the Divine Judgment, that is, as we say today, the awarding of justice. In this spirit, I can say that it was the inevitable coming of this mythical deity that followed the crimes of the communists. Right after the defeat of ELAS in the battle of Athens in December 1944, the authorities began to arrest the perpetrators of the thousands of murders committed during the Axis Occupation throughout the country and the Dekemvriana. Many of the perpetrators either hid in the mountains or fled to Yugoslavia. The approximately 1000 arrested individuals were brought before the criminal courts, where they were tried with full procedural guarantees in the first and second degree. A few were sentenced to death, while others were either acquitted or given lesser sentences. In December 1945, the government passed a "prison decongestion" law which released thousands of people suspected of committing various crimes during the years 1943-1944. Those released from prison either fled to the mountains to escape the wrath of their victims or were murdered or abused by these victims and their relatives. In the courts, it was very difficult to prove with procedural evidence the guilt of the accused because there were no witnesses in these murders. That is why a large number of the accused in the criminal courts were acquitted.

The treatment of the communists who participated in the civil war of 1946-1949 was completely different. The military courts used summary procedures and, depending on whether the arrested person was a member of the KKE or a simple rebel who was most often recruited by force, the death penalty or other lighter sentences were imposed, or the accused was acquitted accordingly. From 1945 to 1953, approximately 52,000 citizens were brought to justice on the charge of having participated in criminal or seditious acts between 1943 and 1950. Of these, 25,000 were acquitted, 14,000 were sentenced to death, and the rest to lesser sentences. Of those sentenced to death, 3000 communists were executed. The rest of those sentenced to death had their sentences commuted. The five-judge military courts for the implementation of the death penalty had the customary behavior of "self-binding leniency". That meant that if a defendant was convicted unanimously, he was executed within three days. If he was convicted by 4-1 votes, he was given the possibility to request a pardon, while if he was convicted by 3-2, his sentence was automatically converted into a multi-year prison term. Although the civil war began in mid-1946, the KKE was outlawed and all its organizations disbanded only in December 1947, when its leadership proceeded to form a provisional government. Thousands of its members were displaced to islands in the Aegean Sea, while after the defeat in August 1949, a total of 85,000 rebels and entire leftist families left for the countries of Eastern Europe. They began to return en masse after the fall of the dictatorship in 1974.

Greece emerged from the civil war economically devastated, with the countryside abandoned due to the military operations. Thanks to the Marshall Plan, the country was able to and did begin its reconstruction. Its population in the 1941 census was 7,344,860 inhabitants, and in 1951 7,632,801 inhabitants, while the region of the Dodecanese – previously part of Italy – was also annexed in 1948. It should be noted that in the census of 1928, Greece’s population amounted to 6,204,684.

From 1950 to 1974 the Greek state honored the victims of the communists with various events. The memories were intense, and several of the protagonists who fought on the side of the national army published their memoirs about the "gang war", as the conflict of 1943-1949 was called. After the fall of the dictatorship – which massively purged the Left – in July 1974 and the consequent legalization of the KKE in September 1974, these celebrations gradually degenerated, while leftist intellectuals began to rewrite and impose their view of the history of the civil war in the context of a wider ideological struggle. After the defeat of 1949 and the oppression they suffered during the post-civil war system of power in Greece, the Left took advantage of the political change following 1974, the so-called Metapolitefsi, and used the dynamic for its overall vindication. Morally, politically and ideologically. The discourse of its intellectuals – “orthodoxes” or “reformists” – dominated for thirty years, and only relatively recently has the so-called revisionist school begun to appear, which again speaks of red terrorism.

Sakis Moumtzis (b. 1953, Thessaloniki) is a researcher and author specializing in Greek political history. He has written books such as The Red Violence 1943-1946: The Memory and Oblivion of the Left and The Red Violence 1947-1950: Guilty Silences, Leftist Myths.