The Dekemvriana (Δεκεμβριανά, "December events") refers to a series of clashes fought during World War II in Athens from 3 December 1944 to 11 January 1945. The conflict was the culmination of months of tension between the communist EAM, some parts of its military wing, the ELAS stationed in Athens, the KKE and the OPLA from one side and from the other side, the el, some parts of the Hellenic Royal Army, the Hellenic Gendarmerie, the Cities Police, the far-right Organization X, among others and also the British Army.
Regardless of the tensions between the left and the right, in May 1944 it had been roughly agreed in the Lebanon Conference that all non-collaborationist factions would participate in a Government of National Unity; eventually 6 out of 24 ministers were appointed by EAM. Additionally, a few weeks before the withdrawal of the German troops in October 1944, it had been reaffirmed in the Caserta Agreement that all collaborationist forces would be tried and punished accordingly; and that all resistance forces would participate in the formation of the new Greek Army, under the command of the British. Yet, on December 1, the British commander Ronald Scobie ordered the unilateral disarmament of EAM-ELAS. The EAM ministers resigned on the 2nd of December and EAM called for a rally in central Athens on the 3rd, requesting the immediate punishment of the collaborationist Security Battalions and the withdrawal of the "Scobie order". The rally of some 200,000 people was shot at by the Greek Police and Gendarmerie, leaving 28 protesters dead and 148 wounded. These killings ushered a full-blown armed confrontation between EAM and the Government forces at first (which included the Security Battalions), and during the second half of December, between EAM and the British military forces.
The clashes were limited to Athens, while elsewhere in Greece the situation remained tense but peaceful, with the exception of Epirus where Aris Velouchiotis attacked the forces of Napoleon Zervas.