Greece had emerged victorious from the 1912-1913
Balkan Wars, with her territory almost doubled, but found itself in a difficult international situation. 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. In the north,
Bulgaria, defeated in the
Second Balkan War, harbored revanchist plans against Greece and
Serbia. The two countries were bound by a treaty of alliance which promised military assistance in case of a Bulgarian attack, but in August 1914, the danger would emerge from a different quarter altogether: the
Assassination of Archduke Franz Ferdinand led to the declaration of war by
Austria-Hungary on Serbia and the outbreak of the
First World War. , June 1916 , September 1916 Greece, like Bulgaria, initially maintained neutrality, but as the war continued, both warring camps began wooing the two countries. At this point the first rifts appeared among the Greek leadership:
Prime Minister Eleftherios Venizelos, at the helm since 1910 of a modernising government looking towards the
British and
French models, supported entry in the war on the side of the
Entente, while King
Constantine I, who had been educated in
Germany, married to Kaiser
Wilhelm II's sister and a deep admirer of
Prussian militarism, anticipated a German victory. Aware that Greece was vulnerable to the
British Fleet, he advocated a course of neutrality. In early 1915 the British offered Greece "territorial concessions in
Asia Minor" if it would participate in the upcoming
Gallipoli Campaign. Venizelos supported this idea, but run into the opposition from the King and his military advisors. As a result, Venizelos submitted his resignation on , and was replaced by a led by
Dimitrios Gounaris. The
Liberal Party won the subsequent
May 1915 elections and Venizelos again formed a on . When Bulgaria mobilized against Serbia in September 1915, Venizelos ordered a Greek counter-mobilization and called upon the Anglo-French to establish themselves in
Thessaloniki (then widely known as
Salonica) as to aid Serbia. Indeed, the Allies began landing on 22 September 1915 and started entrenching themselves at the . The King unconstitutionally dismissed Venizelos and the parliament, making the breach between the two men and their followers irreparable. The Liberals boycotted the
December 1915 elections. In the same month, the French, with the permission of Venizelos, occupied
Corfu, where the remains of the Serbian Army were gathered before being sent to Thessaloniki. In view of these events, a clandestine "Revolutionary Committee of National Defence" was formed in Thessaloniki by a group of prominent Liberals and representatives of all over
Macedonia, including
Konstantinos Angelakis (
mayor of Thessaloniki), and (representatives of
Thessaloniki), and (representatives of
Serres),
Nikolaos Manos (representative of
Kozani),
Panayiotis Grekos (representative of
Florina), (representative of
Drama), Major General
Emmanouil Zymvrakakis and others. The group acknowledged Venizelos as its leader, and began approaching officers of the Army and the
Cretan Gendarmerie. During the following year, Greece's official governments were hard-pressed to maintain the country's neutrality. The final straw came when, on , the Athens government, succumbing to
German pressure, ordered the surrender of the vital
Rupel Fortress to the Germans and their Bulgarian Allies. In response, on , the pro-Entente Venizelists imposed martial law, effectively abolishing royal sovereignty in all of northern Greece. On , the
Bulgarian invasion of eastern
Macedonia commenced, facing little resistance, since the Athens government refused to condone any firm action. As a result, more than 6000 men of
IV Corps surrendered to the Germans on and were deported to
Görlitz in Germany. This surrender of hard-won territories with only token resistance, outraged most Greeks. At the same time, the establishment of the exiled
Serbian King and his government in Thessaloniki in April, the presence of 120,000 Serbian troops in the Macedonian Front, accompanied by threats from the Entente that he would install a Serbian prefect in the city, raised fears that the city would be handed over to the Serbians. ==Uprising in Thessaloniki==