Greece, a state of 2,666,000 people in 1912, was considered the weakest of the three main Balkan allies, since it fielded the smallest land army and had suffered a humiliating defeat against the Ottomans 16 years before in the Greco-Turkish War of 1897. Following the defeat, starting in 1904 and especially after the Goudi coup of 1909, serious efforts were undertaken to reorganize and modernize the Army. From 1911, this task was undertaken by a French military mission. The peacetime establishment of the Hellenic Army in 1912 comprised four infantry divisions newly reformed as triangular divisions, a cavalry brigade, six Evzones battalions, four field artillery and two mountain artillery regiments, one heavy artillery battalion and various support units, including two engineer regiments and an aircraft company. From 25 March 1912, Crown Prince Constantine assumed the position of Inspector-General of the Army, becoming its de facto commander-in-chief.
Mobilization
The army was still in the process of reorganization when the war began. With the escalation of the crisis between the Balkan states and the Ottoman Empire, on, a general mobilization was declared. The existing units were brought up to full complement, and the 5th, 6th, and 7th infantry divisions were set up. This brought the peacetime establishment of ca. 25,000 men up to ca. 110,000. In contrast to pre-war planning, no army corps were established; instead, the divisions were directly subordinated to GHQ. The available forces were grouped into two main commands: the Army of Thessaly, under the Crown Prince, which comprised the bulk of the Greek Army, and the Army of Epirus, under Lt GenKonstantinos Sapountzakis.
Army of Thessaly
The Army of Thessaly comprised in total 59 infantry and 4 Evzone battalions, eight cavalry companies, seven engineer companies, 32 artillery batteries with 96 field guns, 24 mountain guns and 70 machine-guns, and various support troops including an aviation company with four aircraft. The force totalled some 100,000 men, with ca. 80,000 effectives. On these were organized in the following formations:
The Army of Epirus was tasked with the secondary strategic direction, towards the strongly fortified city of Ioannina and beyond. As the main initial strategic effort was to be against Thessaly, it was relegated to a secondary role, and was initially outnumbered by the Ottoman forces in the area. It nevertheless pushed back the initial Ottoman assaults, took Preveza and advanced to the approaches of the Ioannina fortified zone. Two attacks on the city in December and January were repulsed by the Ottoman forces, but after extensive preparations and transfer of forces from Macedonia, the city fell following the Battle of Bizani. The Army of Epirus was commanded until by Lt Gen Konstantinos Sapountzakis, and thereafter by Crown Prince Constantine.
The Army of Epirus was composed of several independent units of roughly divisional strength. Its forces numbered eight infantry and Evzone battalions, one cavalry company and 24 guns, totalling some 10,000–13,000 in the early phases of the war. At the outbreak of the war, it comprised the following units:
15th Infantry Regiment
3rd Evzone Battalion
7th Evzone Battalion
10th Reserve Evzone Battalion
2nd National Guard Battalion
To these were later added two battalions of Cretans, as well as the volunteer Garibaldini legion. On, these forces formed the Epirus Division, renamed in February 1913 as the 8th Infantry Division. In early December, the Army of Epirus was reinforced with the 2nd Infantry Division, followed on 27 December by the 4th Division, by mid-January by the 6th Division and the 7th Infantry Regiment. In preparation for the Battle of Bizani, the Crown Prince brought in additional troops and artillery, while a Mixed Brigade was formed to attack the fortifications of Ioannina from the northeastern flank.
Order of battle before the Battle of Bizani
Before the Battle of Bizani, the Army of Epirus comprised the 2nd, 4th, 6th and 8th Infantry Divisions, the Mixed Brigade, a cavalry regiment and the three independent detachments of Acheron, Preveza and Himara, in total 51 infantry battalions and other units, comprising 41,400 men with 48 machine guns and 93 field and mountain guns. These were grouped as follows, from the right to the left of the Greek front:
First Army Detachment, under Lt Gen Konstantinos Sapountzakis, on the right of the Greek front:
*Mixed Metsovon Brigade, under Col Ioannis Papakyriazis, formed from the 4th Infantry Regiment and the Metsovon Detachment of Lt Col. Mitsas plus other units, in total six battalions, six machine guns and eight mountain guns
*6th Infantry Division, under Col Konstantinos Miliotis-Komninos
**three battalions
**12 field guns
*8th Infantry Division, under Col Dimitrios Matthaiopoulos
**Cretan Regiment, of 3 battalions and four machine guns
**2nd Evzone Regiment, of 2 battalions and eight machine guns
**8 field guns and four machine guns
2nd Infantry Division, under Maj Gen Konstantinos Kallaris, comprising four and a half battalions, eight machine guns, twelve field guns and a cavalry half-company.
Second Army Detachment, under Maj Gen Konstantinos Moschopoulos, CO of the 4th Infantry Division on the left of the Greek front. It comprised mainly the 4th Division plus units from the other divisions, organized in three columns:
*First Column under Col Dimitrios Antoniadis, with six battalions, eight machine guns and eight mountain guns
*Second Column under Col Ioannis Giannakitsas, with eight battalions, fourteen machine guns and eight mountain guns
*Third Column under Col Nikolaos Delagrammatikas, with six battalions, eight machine guns, 10 mountain guns, a cavalry half-company
**Olitsikas Detachment of three battalions
Army Reserve or independent units within the Army's operational zone:
*Epirus Cavalry Regiment, of three companies and two machine guns
*Army Artillery, of six field and two heavy batteries, with 34 guns
*Acheron Detachment of 4 battalions, 4 machine guns and five field guns, at Paramythia
*Preveza Detachment of two battalions, around Preveza and Filippiada
*Himara Detachment of one battalion, two machine guns and two field guns, at Himara
