Greece during World War I

The disagreement between King Constantine, who favoured neutrality, and the pro-Allied Prime Minister Eleftherios Venizelos led to the National Schism, the division of the state between two rival governments.

The status of the Greek-occupied eastern Aegean islands was left undetermined and the Ottoman Empire continued to claim them, leading to a naval arms race and mass expulsions of ethnic Greeks from Anatolia (Asia Minor).

[1] However, in the spring and summer of 1914, Greece found itself in a confrontation with the Ottoman Empire over the status of the eastern Aegean islands, coupled with a naval race between the two countries and persecutions of the Greeks in Asia Minor.

Thus, once Romania declared its neutrality and refused to undertake any commitments in the event of a Bulgarian attack on Serbia, Greece could not count on Romanian assistance against Bulgaria or the Ottomans, and was, in the view of Venizelos, effectively left diplomatically isolated in the region.

[8] King Constantine I on the other hand, backed by Foreign Minister Georgios Streit and the General Staff, were convinced of Germany's eventual triumph and furthermore sympathized with the German militarist political system.

[9] The thinking of Streit, the King's main political advisor on the subject, was influenced by his fear of pan-Slavism (in the first instance Bulgaria, but ultimately represented by Russia) against which Germany supposedly fought, as well as by his belief that the traditional European balance of power would not be upset by the war, leaving little room for territorial gains by Greece in the event of her participation in the conflict.

The Greek prime minister argued that an important clause in the alliance agreement was rendered impossible: Serbia had undertaken to provide 150,000 troops in the area of Gevgelija to guard against a Bulgarian attack.

The plan led nowhere, primarily due to Russian involvement in the affairs of Bulgaria and Serbia, but it did signal that Venizelos was ready to abandon the territorial status quo as long as Greek interests were safeguarded.

Venizelos' diplomatic initiative ran contrary to the Allies' intentions at the time, which were focused on enticing Bulgaria to join their cause, even offering her territorial concessions at the expense of Serbia, Romania, and Greece.

Venizelos anticipated a Bulgarian attack on Serbia either as a member of the Central Powers or independently; since that would be contrary to Greek interests, Greece's entry into the war on the Allies' side was only a matter of time.

[26] While 24 classes of men were called to arms, the mobilization proceeded with numerous difficulties and delays, as infrastructure or even military registers were lacking in the areas recently acquired during the Balkan Wars.

[27] As the likelihood of a Bulgarian entry into the war on the side of the Central Powers loomed larger, the Serbs requested Greek assistance in virtue of the terms of the treaty of alliance.

Venizelos, however, asked the French ambassador to send Allied troops to Thessaloniki as quickly as possible, but to give a warning of 24 hours to the Greek government; Greece would lodge a formal complaint at the violation of its neutrality, but then accept the fait accompli.

When the Allied warships arrived in the Thermaic Gulf on the morning of 30 September, the local Greek commander, the head of III Corps, Lt. General Konstantinos Moschopoulos, unaware of the diplomatic manoeuvres, refused them entry pending instructions from Athens.

When the Serbian staff colonel Milan Milovanović visited Athens to elicit the new government's intentions, Metaxas informed him that if Greece sent two army corps to Serbia, eastern Macedonia would be left defenceless, so that the line of communication of both the Serbs and the Greek forces would be cut off by the Bulgarians.

[36] As a result, though under constant pursuit, the remnants of the Serbian army retreated into Albania, aiming to reach the shores of the Adriatic, while Sarrail ordered his own forces to withdraw south towards Thessaloniki, re-crossing the Greek frontier on 13 December 1915.

Although the Austrian commander Franz Conrad von Hötzendorf pressed to complete the victory in Serbia by clearing Albania and evicting the Allies from Thessaloniki, and forcing Greece and Romania to enter the war on the side of the Central Powers, the German high command, under Erich von Falkenhayn, was eager to end operations so as to focus on his plan to win the war by bleeding the French army dry at the Battle of Verdun.

[38] In the meantime, Greece descended further into political crisis: on the night of 3–4 November, the Zaimis government was voted down in Parliament, in a session in which the Minister of Military Affairs and a Venizelist MP came to blows.

[41] This space was left to be defended by three French and five British divisions,[42] which in December 1915–January 1916 entrenched themselves in a broad arc around Thessaloniki, from the Gulf of Orfanos in the east to the Vardar river in the west.

[47] While Athens tried to maintain a balance between the warring coalitions and defend what remained of the country's neutrality, the Allies imposed a limited embargo on coal and wheat imports and seized Lesbos on 28 December for use as a base of operations.

[61] The French played the leading role in these events, led by Sarrail and ambassador Jean Guillemin, who pressed for no less than the overthrow of King Constantine, while the British opposed such extreme measures.

The Central Powers' advance continued in the west, where they clashed not only with the Serbians around Kajmakčalan, but also with the Greek 18th Infantry Regiment, as well as in eastern Macedonia, where Bulgarian forces crossed the Nestos river at Chrysoupolis, and approached Kavala.

It received no answer,[67] and as a result, the government decided not to offer resistance to the Bulgarian advance in eastern Macedonia, where the Greek position was precarious: following demobilization, IV Corps was left with c. 600 officers and 8,500 men, headed by the 7th Division commander, Colonel Ioannis Hatzopoulos, while the fortifications of the Kavala Fortress area had not been completed.

Colonel Konstantinos Mazarakis, and with the encouragement and support of Sarrail, had been engaged in a conspiracy to foment a revolt among the Greek military forces in Macedonia and lead them into war against Bulgaria.

The regular Greek military units mostly proved loyal to the government, but Moschopoulos' deputy, Colonel Nikolaos Trikoupis, sought to avoid bloodshed and a direct confrontation with the Allies.

However, within a few days they were joined by other uprisings led by local politicians at Chania, Herakleion, and Samos; in all cases, the loyalist officers were expelled and the entry of Greece into the war on the side of the Allies demanded.

During the same night, embarkation resumed in great disorder, but when Hatzopoulos himself approached a British vessel, a representative of the National Defence informed him that the ship's captain a pledge of support to the Thessaloniki regime before he could be allowed on board.

[80] On the morning of the next day, the Germans informed Hatzopoulos that they agreed to accept to move the IV Corps to Germany, where they would be interned as "guests" rather than prisoners of war, with their personal weapons.

[88] The Greek forces in the area, 16th Division under V Corps, had been scaled down considerably following the June demobilization, and its commander, Major General Georgios Mavrogiannis, was unable to offer any effective resistance.

Greece, by now united under a single government, officially declared war against the Central Powers on 30 June 1917 and would eventually raise 10 divisions for the Entente effort, alongside the Royal Hellenic Navy.