Greece during World War I (two)
However, in February, 1915, the Allied attack on Gallipoli began, with naval bombardments of the Ottoman forts there. Venizelos decided to offer an army corps and the entire Greek fleet to assist the Allies, making an official offer on 1 March, despite the King's reservations. This caused Metaxas to resign on the next day, while meetings of the Crown Council (the King, Venizelos, and the living former prime ministers) on 3 and 5 March proved indecisive. King Constantine decided to keep the country neutral, whereupon Venizelos submitted his resignation on 6 March 1915. This time it was accepted, and he was replaced by Dimitrios Gounaris, who formed his government on 10 March. On 12 March, the new government suggested to the Allies its willingness to join them, under certain conditions. The Allies, however, expected a victory of Venizelos in the forthcoming elections and were in no hurry to commit themselves. Thus on 12 April, they replied to Gounaris' proposal, offering territorial compensation in vague terms the Aydin Vilayet—anything more concrete was impossible since at the same time the Allies were negotiating with Italy on her own demands in the same area—while making no mention of Greece's territorial integrity vis-a-vis Bulgaria, as Venizelos had already proven himself willing to countenance the cession of Kavala to Bulgaria.
The Liberal Party won the 12 June elections, and Venizelos again formed a government on 30 August, with the firm intention of bringing Greece into the war on the side of the Allies. In the meantime, on 3 August, the British formally requested, on behalf of the Allies, the cession of Kavala to Bulgaria; this was rejected on 12 August, before Venizelos took office.
On 6 September, Bulgaria signed a treaty of alliance with Germany, and a few days later mobilized against Serbia. Venizelos ordered a Greek counter-mobilization on 23 September. 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. Five army corps and 15 infantry divisions were eventually mobilized, but there were insufficient officers to man all the units, reservists tarried in presenting themselves to the recruiting stations, and there was a general lack of means of transport to bring them to their units. In the end, only the III, IV, and V Corps were assembled in Macedonia, while the divisions of I and II Corps largely remained behind in "Old Greece". Likewise, III Corps' 11th Infantry Division remained in Thessaloniki, rather than proceeding to the staging areas along the border.
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. Again, however, the issue of Serbian assistance against Bulgaria around Gevgelija was raised: even after mobilization, Greece could muster only 160,000 men against 300,000 Bulgarians. As the Serbs were too hard-pressed to divert any troops to assist Greece, on 22 September Venizelos asked the Anglo-French to assume that role. The Allies gave a favourable reply on 24 September, but they did not have the 150,000 men required; as a result, the King, the Army Staff Service, and large part of the opposition preferred to remain neutral until the Allies could guarantee effective support. 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. As a result, the French 156th Division and the British 10th Division were ordered to embark from Gallipoli for Thessaloniki.
However, the Allies failed to inform Athens, leading to a tense stand-off. 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. Venizelos was outraged that the Allies had not informed him as agreed, and refused to allow their disembarkation. After a tense day, the Allies agreed to halt their approach until the Allied diplomats could arrange matters with Venizelos in Athens. Finally, during the night of 1–2 October, Venizelos gave the green light for the disembarkation, which began on the same morning. The Allies issued a communique justifying their landing as a necessary measure to secure their lines of communication with Serbia, to which the Greek government replied with a protest but no further actions.
Following this event, Venizelos presented to Parliament his case for participation in the war, securing 152 votes in favour to 102 against on 5 October. On the next day, however, King Constantine dismissed Venizelos and called upon Alexandros Zaimis to form a government. Zaimis was favourably disposed to the Allies, but the military situation was worse than a few months before: the Serbs were stretched to breaking point against the Austro-Germans, Romania remained staunchly neutral, Bulgaria was on the verge of entering the war on the side of the Central Powers, and the Allies had few reserves to provide any practical aid to Greece. 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. Metaxas proposed instead a joint offensive against Bulgaria, with the Greeks attacking along the Nestos and Strymon valleys, the Allies from the Vardar valley, and the Serbs joining in. Milovanović informed Metaxas that the pressure on the Serbian Army left them unable to spare forces for any such operation. On 10 October, the Zaimis government officially informed Serbia that it could not come to her aid. Even an offer of Cyprus by the British on 16 October was not enough to alter the new government's stance.
Indeed, on 7 October the Austro-German forces under August von Mackensen began their decisive offensive against Serbia, followed by a Bulgarian attack on 14 October, without prior declaration of war. The Bulgarian attack cut off the Serbian retreat south to Greece, forcing the Serbian army to retreat via Albania. The French commander-designate in Thessaloniki, Maurice Sarrail, favoured a large-scale Allied operation in Macedonia against Bulgaria, but available forces were few; the British especially were loath to evacuate Gallipoli, while the French commander-in-chief, Joseph Joffre, was reluctant to divert forces from the Western Front. In the end, it was agreed to send 150,000 troops to the "Salonika front", approximately half each French—the "Armée d'Orient" under Sarrail, with the 156th, 57th, and 122nd divisions—and British—the "British Salonika Force" under Bryan Mahon, with 10th Division, XII Corps and XVI Corps.
On 22 October, the Bulgarians captured Skopje, thus cutting off the Serbs from the Allied forces assembling in Thessaloniki. In an attempt to link up with the retreating Serbs, Sarrail launched an attack against Skopje on 3–13 November, but the French government ordered him to stop his advance. A Serbian attack on the 20th was fought off by the Bulgarians, and any hope of the Serbs linking up with Sarrail's forces evaporated. 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. As the Bulgarians followed closely behind the Allies and attacked them during their retreat, there was concern that they would simply continue on past the border. Lt. General Moschopoulos' requests for instructions to Athens went unanswered, but on his own initiative he deployed the 3/40 Evzone Regiment to cover the border with at least a token force. In the event, the Central Powers halted before the Greek border, for the time being. 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.
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. King Constantine named Stefanos Skouloudis as the new Prime Minister, with the same cabinet; the new prime minister took over the Ministry of Foreign Affairs himself. On 11 November, Parliament was dissolved again and elections set for 19 December.
The new government was pressured by Germany and Austria not to allow the Allies to withdraw into Greek territory, to which Skouloudis replied that Greece would implement the terms of the Hague Conventions, according to which the Allied forces would have to be disarmed once crossing into Greek soil. This created uproar among the Allied governments, who began clamouring for the evacuation of the Greek army from Macedonia, and the occupation of Milos and Piraeus by the Allied navies. Meanwhile, Greek merchant shipping was detained in Allied harbours and an unofficial embargo placed on Greece. On 19 November, the Greek government informed the Allies that their forces would not be disarmed, and that Greek forces in Macedonia were there to defend against Bulgarian attack rather than interfere with the Allies. Nevertheless, on 21 November the Allies occupied Milos, and two days later demanded formal and categorical assurances that their forces would enjoy freedom of movement and action in and around Thessaloniki; Skouloudis accepted, but two days later, the demands were upped, by demanding the removal of the Greek army from Thessaloniki, the placing of all roads and railroads in the direction of Serbia under Allied disposal, the permission to fortify the environs of Thessaloniki and Chalcidice, and unrestricted movement of the Allied fleets in Greek waters.
Following negotiations on 9–10 December at Thessaloniki between Sarrail and Mahon on the one side and Moschopoulos and Lt. Colonel Konstantinos Pallis on the other, a compromise was achieved: the Greek 11th Division would remain in Thessaloniki, and the Karabournou Fortress would remain in Greek hands; on the other hand, the Greek government promised not to interfere with any Allied measures to fortify their positions, and would remain neutral if Allied activity caused a third power to invade Greek territory. The Allies withdrew from Milos, while the Greek V Army Corps was moved east towards Nigrita, leaving the area between Thessaloniki and the northern Greek border devoid of troops.
This space was left to be defended by three French and five British divisions, 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. The eastern portion of this front was held by the British, and the western third by the French. On 16 January 1916, Sarrail was appointed Allied commander-in-chief in Macedonia. The bulk of the Greek forces in the area assembled in eastern Macedonia (IV Army Corps east of the Strymon River, V Corps in the Nigrita area, and some support units of the I and II Corps around Mount Vermion). These forces faced the First and Second Bulgarian Armies.
On the Central Powers' side, on 29 November 1915, Falkenhayn had publicly threatened that if Greece could not neutralize the Allied and Serbian forces on its soil, the Germans and their allies would cross the border and do it for them, and on 10 December, the German Foreign Ministry reacted to the new agreement between Greece and the Allies regarding their armies in Macedonia by demanding the same rights of free movement in Greek territory. To these demands, the Greek government answered on 22 December that it would not actively oppose a Central Powers invasion of its territory, provided that the Bulgarians did not participate or at least stayed out of the cities, and the command of the operations was in German hands; that Bulgaria issued no territorial demands; that the Central Powers forces would withdraw once their objectives were met; and that the Greek authorities remain in place.
On 6 January, Germany declared its willingness to respect Greek sovereignty, provided that the Greek army withdrew from the border area, with its bulk retiring west behind the Lake Prespa–Katerini line, leaving only V Corps in the Kavala area, and that any Allied attempts to land at either Kavala or Katerini were to be resisted. In this way, Macedonia would be left uncontested for the Allies and Central Powers to fight, while the remainder of Greece remained neutral. In late January, the Greek government submitted a broadly similar proposal, developed by Metaxas, to the Allies; while the British military attache and Sarrail initially accepted it, the French government decided to reject it, regarding it as a trap: the evacuation of the Nigrita–Drama area would expose the Allied flank to Bulgarian attacks, while conversely, the presence of the Greek army in Katerini would cover the Germans' right flank. Furthermore, by the terms of Metaxas' proposal, the Allies would lose access to the ports of Katerini and Volos.
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. On the same day, three German airplanes bombed British positions in Thessaloniki, after which Sarrail arrested all foreign consuls in the city and detained them on an Allied warship. Allied encroachments on Greek sovereignty continued to gather pace: on 10 January 1916, the Allied ambassadors announced that the Serbian troops would be ferried from Albania to the Greek island of Corfu, which was seized by French troops on the next day. In order to impede a possible Bulgarian advance, on 12 January, Sarrail ordered several railway bridges blown up, and on 28 January, French troops seized the Karabournou Fortress to control the entry to the Thermaic Gulf. Both steps were taken without the agreement of the Greek authorities or even consultation with General Mahon, but enraged Greek public opinion, which began to turn against the Allies.
The whole series of events in the winter of 1915/1916 was indicative of the hopeless legal and political imbroglio that the Greek government found itself. This was now firmly in the hands of the anti-Venizelist faction, as Venizelos and his supporters boycotted the elections of 19 December. The already tense political situation in Greece was worsened by the active propaganda carried out by the warring coalitions, with the Central Powers stoking resentment at heavy-handed Allied actions, and the Allies urging Greece to side with them against its traditional rivals, the Bulgarians and the Turks. As the original guarantor powers of Greece, Britain, France, and Russia further claimed a right to intervene as the Greek government had violated both the alliance with Serbia and the Greek constitution by organizing what the Allies (and the Venizelists) regarded as illegal elections.
The mistrust between Sarrail and the Greek government was evident on 23 February when he visited King Constantine and Skouloudis to explain his unilateral actions in Macedonia. By that time, 133,000 Serbian soldiers had been evacuated to Corfu. Over 3,000 died of dysentery and typhus during their stay there, but they were also re-equipped with French arms and formed into six divisions. The Allies planned to move them to Macedonia, and consequently, on 5 April, they demanded that they be moved by ship to Patras and thence overland by rail, via Athens and Larissa, to Thessaloniki. Skouloudis vehemently rejected this request, and a heated quarrel with the French ambassador ensued. The breach between the Greek and Allied governments was further deepened when the French rejected a request for a 150 million Franc loan on 23 April, only for Athens to agree to a similar loan from Germany instead.
In the event, the Serbian army was moved by ship to Macedonia, where it was grouped into three field armies. The addition of the 130,000 Serbs gave the Allies over 300,000 men in Macedonia, raising the prospect of an Allied offensive that might draw Romania into the war on the Allied side. This was delayed as the demands placed by the ongoing Battle of Verdun on the Western Front did not allow the transfer of more troops to Macedonia, but conversely, the Allies sought to tie down German and Austrian forces that had begun to withdraw in Macedonia. As a result, on 12 March 1916, the Allied forces exited the Salonica camp and approached the Greek frontier, where they came into contact with Central Powers forces.
On 14 March, Falkenhayn informed the Greek government that German-Bulgarian troops would advance up to Neo Petritsi. The Ministry of Military affairs immediately issued orders for all covering forces to be withdrawn so as to avoid contact with the German–Bulgarian forces. If the latter targeted Greek forts, the latter had to be evacuated and their armament destroyed. However, on 10 May, this order was rescinded as the government feared lest the Bulgarians take advantage of it unilaterally, and the Greek forces were ordered to oppose with arms any incursion of more than 500m into Greek soil.
On the same day, two events of major importance occurred. First, French battalions seized the Greek fort of Dova Tepe, located between lakes Doiran and Kerkini. The garrison provided no resistance, in accordance with its instructions. In the wake of this, the Greek forces evacuated the area from the Vardar to Dova Tepe. As a result, the Greek forces found themselves in two widely separate concentrations: V Corps (8th, 9th, 15th Divisions) and IV Corps (5th, 6th, 7th Divisions) in eastern Macedonia, and III Corps (10th, 11th, 12th Divisions) and the Greek forces in Thessaly to the west. Second, the Germans notified Athens that they wanted to occupy the Rupel Pass, east of Lake Kerkini, in response to the Allies' crossing the Strymon River. The Greek government protested that this was not the case, but on 22 May 1916, the Bulgarian and German governments formally notified Athens of their intention to occupy Rupel.
On 26 May, the garrison of the Rupel Fortress detected approaching German-Bulgarian columns. Its commander, Major Ioannis Mavroudis, after notifying his superiors (6th Division and Thessaloniki Fortress Command), informed the approaching Germans of his orders to resist. The 6th Division commander, Major General Andreas Bairas, mobilized his forces and issued orders to resist any attack, while sending word to Athens, IV Corps, and notifying the Allied forces that had advanced up to the village of Strymoniko (about 40 kilometres (25 mi) to the south) for possible assistance. Despite repeated warnings that they would resist any attempt to seize Rupel and that Athens had been notified, three German-Bulgarian columns moved to capture Mount Kerkini, Mount Angistro, and the bridge over the Strymon at Koula, until Mavroudis ordered
The Liberal Party won the 12 June elections, and Venizelos again formed a government on 30 August, with the firm intention of bringing Greece into the war on the side of the Allies. In the meantime, on 3 August, the British formally requested, on behalf of the Allies, the cession of Kavala to Bulgaria; this was rejected on 12 August, before Venizelos took office.
On 6 September, Bulgaria signed a treaty of alliance with Germany, and a few days later mobilized against Serbia. Venizelos ordered a Greek counter-mobilization on 23 September. 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. Five army corps and 15 infantry divisions were eventually mobilized, but there were insufficient officers to man all the units, reservists tarried in presenting themselves to the recruiting stations, and there was a general lack of means of transport to bring them to their units. In the end, only the III, IV, and V Corps were assembled in Macedonia, while the divisions of I and II Corps largely remained behind in "Old Greece". Likewise, III Corps' 11th Infantry Division remained in Thessaloniki, rather than proceeding to the staging areas along the border.
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. Again, however, the issue of Serbian assistance against Bulgaria around Gevgelija was raised: even after mobilization, Greece could muster only 160,000 men against 300,000 Bulgarians. As the Serbs were too hard-pressed to divert any troops to assist Greece, on 22 September Venizelos asked the Anglo-French to assume that role. The Allies gave a favourable reply on 24 September, but they did not have the 150,000 men required; as a result, the King, the Army Staff Service, and large part of the opposition preferred to remain neutral until the Allies could guarantee effective support. 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. As a result, the French 156th Division and the British 10th Division were ordered to embark from Gallipoli for Thessaloniki.
However, the Allies failed to inform Athens, leading to a tense stand-off. 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. Venizelos was outraged that the Allies had not informed him as agreed, and refused to allow their disembarkation. After a tense day, the Allies agreed to halt their approach until the Allied diplomats could arrange matters with Venizelos in Athens. Finally, during the night of 1–2 October, Venizelos gave the green light for the disembarkation, which began on the same morning. The Allies issued a communique justifying their landing as a necessary measure to secure their lines of communication with Serbia, to which the Greek government replied with a protest but no further actions.
Following this event, Venizelos presented to Parliament his case for participation in the war, securing 152 votes in favour to 102 against on 5 October. On the next day, however, King Constantine dismissed Venizelos and called upon Alexandros Zaimis to form a government. Zaimis was favourably disposed to the Allies, but the military situation was worse than a few months before: the Serbs were stretched to breaking point against the Austro-Germans, Romania remained staunchly neutral, Bulgaria was on the verge of entering the war on the side of the Central Powers, and the Allies had few reserves to provide any practical aid to Greece. 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. Metaxas proposed instead a joint offensive against Bulgaria, with the Greeks attacking along the Nestos and Strymon valleys, the Allies from the Vardar valley, and the Serbs joining in. Milovanović informed Metaxas that the pressure on the Serbian Army left them unable to spare forces for any such operation. On 10 October, the Zaimis government officially informed Serbia that it could not come to her aid. Even an offer of Cyprus by the British on 16 October was not enough to alter the new government's stance.
Indeed, on 7 October the Austro-German forces under August von Mackensen began their decisive offensive against Serbia, followed by a Bulgarian attack on 14 October, without prior declaration of war. The Bulgarian attack cut off the Serbian retreat south to Greece, forcing the Serbian army to retreat via Albania. The French commander-designate in Thessaloniki, Maurice Sarrail, favoured a large-scale Allied operation in Macedonia against Bulgaria, but available forces were few; the British especially were loath to evacuate Gallipoli, while the French commander-in-chief, Joseph Joffre, was reluctant to divert forces from the Western Front. In the end, it was agreed to send 150,000 troops to the "Salonika front", approximately half each French—the "Armée d'Orient" under Sarrail, with the 156th, 57th, and 122nd divisions—and British—the "British Salonika Force" under Bryan Mahon, with 10th Division, XII Corps and XVI Corps.
On 22 October, the Bulgarians captured Skopje, thus cutting off the Serbs from the Allied forces assembling in Thessaloniki. In an attempt to link up with the retreating Serbs, Sarrail launched an attack against Skopje on 3–13 November, but the French government ordered him to stop his advance. A Serbian attack on the 20th was fought off by the Bulgarians, and any hope of the Serbs linking up with Sarrail's forces evaporated. 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. As the Bulgarians followed closely behind the Allies and attacked them during their retreat, there was concern that they would simply continue on past the border. Lt. General Moschopoulos' requests for instructions to Athens went unanswered, but on his own initiative he deployed the 3/40 Evzone Regiment to cover the border with at least a token force. In the event, the Central Powers halted before the Greek border, for the time being. 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.
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. King Constantine named Stefanos Skouloudis as the new Prime Minister, with the same cabinet; the new prime minister took over the Ministry of Foreign Affairs himself. On 11 November, Parliament was dissolved again and elections set for 19 December.
The new government was pressured by Germany and Austria not to allow the Allies to withdraw into Greek territory, to which Skouloudis replied that Greece would implement the terms of the Hague Conventions, according to which the Allied forces would have to be disarmed once crossing into Greek soil. This created uproar among the Allied governments, who began clamouring for the evacuation of the Greek army from Macedonia, and the occupation of Milos and Piraeus by the Allied navies. Meanwhile, Greek merchant shipping was detained in Allied harbours and an unofficial embargo placed on Greece. On 19 November, the Greek government informed the Allies that their forces would not be disarmed, and that Greek forces in Macedonia were there to defend against Bulgarian attack rather than interfere with the Allies. Nevertheless, on 21 November the Allies occupied Milos, and two days later demanded formal and categorical assurances that their forces would enjoy freedom of movement and action in and around Thessaloniki; Skouloudis accepted, but two days later, the demands were upped, by demanding the removal of the Greek army from Thessaloniki, the placing of all roads and railroads in the direction of Serbia under Allied disposal, the permission to fortify the environs of Thessaloniki and Chalcidice, and unrestricted movement of the Allied fleets in Greek waters.
Following negotiations on 9–10 December at Thessaloniki between Sarrail and Mahon on the one side and Moschopoulos and Lt. Colonel Konstantinos Pallis on the other, a compromise was achieved: the Greek 11th Division would remain in Thessaloniki, and the Karabournou Fortress would remain in Greek hands; on the other hand, the Greek government promised not to interfere with any Allied measures to fortify their positions, and would remain neutral if Allied activity caused a third power to invade Greek territory. The Allies withdrew from Milos, while the Greek V Army Corps was moved east towards Nigrita, leaving the area between Thessaloniki and the northern Greek border devoid of troops.
This space was left to be defended by three French and five British divisions, 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. The eastern portion of this front was held by the British, and the western third by the French. On 16 January 1916, Sarrail was appointed Allied commander-in-chief in Macedonia. The bulk of the Greek forces in the area assembled in eastern Macedonia (IV Army Corps east of the Strymon River, V Corps in the Nigrita area, and some support units of the I and II Corps around Mount Vermion). These forces faced the First and Second Bulgarian Armies.
On the Central Powers' side, on 29 November 1915, Falkenhayn had publicly threatened that if Greece could not neutralize the Allied and Serbian forces on its soil, the Germans and their allies would cross the border and do it for them, and on 10 December, the German Foreign Ministry reacted to the new agreement between Greece and the Allies regarding their armies in Macedonia by demanding the same rights of free movement in Greek territory. To these demands, the Greek government answered on 22 December that it would not actively oppose a Central Powers invasion of its territory, provided that the Bulgarians did not participate or at least stayed out of the cities, and the command of the operations was in German hands; that Bulgaria issued no territorial demands; that the Central Powers forces would withdraw once their objectives were met; and that the Greek authorities remain in place.
On 6 January, Germany declared its willingness to respect Greek sovereignty, provided that the Greek army withdrew from the border area, with its bulk retiring west behind the Lake Prespa–Katerini line, leaving only V Corps in the Kavala area, and that any Allied attempts to land at either Kavala or Katerini were to be resisted. In this way, Macedonia would be left uncontested for the Allies and Central Powers to fight, while the remainder of Greece remained neutral. In late January, the Greek government submitted a broadly similar proposal, developed by Metaxas, to the Allies; while the British military attache and Sarrail initially accepted it, the French government decided to reject it, regarding it as a trap: the evacuation of the Nigrita–Drama area would expose the Allied flank to Bulgarian attacks, while conversely, the presence of the Greek army in Katerini would cover the Germans' right flank. Furthermore, by the terms of Metaxas' proposal, the Allies would lose access to the ports of Katerini and Volos.
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. On the same day, three German airplanes bombed British positions in Thessaloniki, after which Sarrail arrested all foreign consuls in the city and detained them on an Allied warship. Allied encroachments on Greek sovereignty continued to gather pace: on 10 January 1916, the Allied ambassadors announced that the Serbian troops would be ferried from Albania to the Greek island of Corfu, which was seized by French troops on the next day. In order to impede a possible Bulgarian advance, on 12 January, Sarrail ordered several railway bridges blown up, and on 28 January, French troops seized the Karabournou Fortress to control the entry to the Thermaic Gulf. Both steps were taken without the agreement of the Greek authorities or even consultation with General Mahon, but enraged Greek public opinion, which began to turn against the Allies.
The whole series of events in the winter of 1915/1916 was indicative of the hopeless legal and political imbroglio that the Greek government found itself. This was now firmly in the hands of the anti-Venizelist faction, as Venizelos and his supporters boycotted the elections of 19 December. The already tense political situation in Greece was worsened by the active propaganda carried out by the warring coalitions, with the Central Powers stoking resentment at heavy-handed Allied actions, and the Allies urging Greece to side with them against its traditional rivals, the Bulgarians and the Turks. As the original guarantor powers of Greece, Britain, France, and Russia further claimed a right to intervene as the Greek government had violated both the alliance with Serbia and the Greek constitution by organizing what the Allies (and the Venizelists) regarded as illegal elections.
The mistrust between Sarrail and the Greek government was evident on 23 February when he visited King Constantine and Skouloudis to explain his unilateral actions in Macedonia. By that time, 133,000 Serbian soldiers had been evacuated to Corfu. Over 3,000 died of dysentery and typhus during their stay there, but they were also re-equipped with French arms and formed into six divisions. The Allies planned to move them to Macedonia, and consequently, on 5 April, they demanded that they be moved by ship to Patras and thence overland by rail, via Athens and Larissa, to Thessaloniki. Skouloudis vehemently rejected this request, and a heated quarrel with the French ambassador ensued. The breach between the Greek and Allied governments was further deepened when the French rejected a request for a 150 million Franc loan on 23 April, only for Athens to agree to a similar loan from Germany instead.
In the event, the Serbian army was moved by ship to Macedonia, where it was grouped into three field armies. The addition of the 130,000 Serbs gave the Allies over 300,000 men in Macedonia, raising the prospect of an Allied offensive that might draw Romania into the war on the Allied side. This was delayed as the demands placed by the ongoing Battle of Verdun on the Western Front did not allow the transfer of more troops to Macedonia, but conversely, the Allies sought to tie down German and Austrian forces that had begun to withdraw in Macedonia. As a result, on 12 March 1916, the Allied forces exited the Salonica camp and approached the Greek frontier, where they came into contact with Central Powers forces.
On 14 March, Falkenhayn informed the Greek government that German-Bulgarian troops would advance up to Neo Petritsi. The Ministry of Military affairs immediately issued orders for all covering forces to be withdrawn so as to avoid contact with the German–Bulgarian forces. If the latter targeted Greek forts, the latter had to be evacuated and their armament destroyed. However, on 10 May, this order was rescinded as the government feared lest the Bulgarians take advantage of it unilaterally, and the Greek forces were ordered to oppose with arms any incursion of more than 500m into Greek soil.
On the same day, two events of major importance occurred. First, French battalions seized the Greek fort of Dova Tepe, located between lakes Doiran and Kerkini. The garrison provided no resistance, in accordance with its instructions. In the wake of this, the Greek forces evacuated the area from the Vardar to Dova Tepe. As a result, the Greek forces found themselves in two widely separate concentrations: V Corps (8th, 9th, 15th Divisions) and IV Corps (5th, 6th, 7th Divisions) in eastern Macedonia, and III Corps (10th, 11th, 12th Divisions) and the Greek forces in Thessaly to the west. Second, the Germans notified Athens that they wanted to occupy the Rupel Pass, east of Lake Kerkini, in response to the Allies' crossing the Strymon River. The Greek government protested that this was not the case, but on 22 May 1916, the Bulgarian and German governments formally notified Athens of their intention to occupy Rupel.
On 26 May, the garrison of the Rupel Fortress detected approaching German-Bulgarian columns. Its commander, Major Ioannis Mavroudis, after notifying his superiors (6th Division and Thessaloniki Fortress Command), informed the approaching Germans of his orders to resist. The 6th Division commander, Major General Andreas Bairas, mobilized his forces and issued orders to resist any attack, while sending word to Athens, IV Corps, and notifying the Allied forces that had advanced up to the village of Strymoniko (about 40 kilometres (25 mi) to the south) for possible assistance. Despite repeated warnings that they would resist any attempt to seize Rupel and that Athens had been notified, three German-Bulgarian columns moved to capture Mount Kerkini, Mount Angistro, and the bridge over the Strymon at Koula, until Mavroudis ordered
