[1][2][3] Mounting tensions between itself and the other rival groups, sparked by ideology as well as EAM-ELAS' ambition to be the sole instrument of "national liberation", led to repeated clashes in 1943–44, in what was later termed the "first phase" of the Civil War.
[4] At the time of Greece's liberation in October 1944, EAM-ELAS dominated the country except for the major cities, especially Athens, where British forces supported the returned Greek government in exile.
The government side failed to fulfill its obligations, while rogue members of KKE such as Aris Velouchiotis hid large caches of weaponry in anticipation of future reprisals by the rightists.
[11] By May 1945, the National Guard had established outposts across the entire country, however its numbers were insufficient to maintain order and the Gendarmerie's manpower was likewise depleted during the Dekemvriana.
[14] After the second party congress of KKE in February 1946, approximately 250 leftist self-defense militias, known as Groups of Democratic Armed Persecuted Fighters (ODEKA), were formed across Greece, totaling some 3,000 men.
Following the victory of the United Alignment of Nationalists on 1 April 1946 and until 1 May of the same year, 116 leftists were murdered, 31 injured, 114 tortured, 4 buildings were set aflame and 7 political offices were ransacked.