Entente occupies Thessaly and the Isthmus of Corinth

The demand for King Constantine’s abdication, which the High Commissioner Charles Jonnart presented on 11 June 1917, was backed by force from the outset. Within a few days the troops of General Maurice Sarrail, commander of the Allied armies in Macedonia, occupied Thessaly, the Isthmus of Corinth and the area around Piraeus. The British chronology of the war records under 12 June that Entente forces occupied Corinth and Larissa. Larissa was indeed taken that day, but on the isthmus the French had already landed on the evening of 10 June, as the British official history of the Macedonian campaign (Falls) and the British writer George F. Abbott state, or during the night of 10 to 11 June, as other accounts have it. On 12 June French troops also went ashore at Piraeus.

Why Thessaly

The French had long wanted to occupy Thessaly, and at the conferences in Paris and London in May 1917 the Allies agreed to it. It was above all about the harvest. The Thessalian grain, which was just ripening, was the only large food supply for royalist Greece, worn down by the blockade. Had it reached the Athens government’s granaries, the blockade would have lost much of its force. John Buchan adds that the left rear of Sarrail’s army had long been troubled by bands of royalist reservists, and that the area had to be secured before the question of the King was settled. The occupation of the Isthmus of Corinth, in turn, was meant to prevent the royal army, which at the Entente’s demand had been moved there in the winter, from marching out of the Peloponnese.

The march on Larissa

According to Greek studies the troops assigned to the expedition were assembled by 7 June near Katerini. They were commanded by General Venel. Falls lists in Thessaly four French cavalry regiments, including Moroccan spahis, an infantry regiment and two territorial battalions. Greek sources put Venel’s forces, with artillery and aircraft, at more than 20,000 men. According to the same studies, the government in Athens ordered its few units in Thessaly, under General Andreas Bairas, not to resist. On the morning of Sunday 10 June the French moved south; on 11 June they took Elassona, and on 12 June they entered Larissa. Bairas rode out to meet Venel to place himself at his disposal, but the French general immediately arrested him together with his staff officers.

At Larissa the only serious clash of the whole operation took place. Falls writes briefly that the French cavalry advancing on the town was fired on and lost two officers and four men killed, after which it quickly routed the attackers, inflicting heavy losses on them and taking more than three hundred prisoners. Buchan calls it “treacherous firing” by a Greek unit. Greek accounts describe it differently. The soldiers of the 1/38 Evzone Regiment of Lieutenant-Colonel Athanasios Frangou, whom the French ordered to lay down their arms, with the officers to surrender their swords, refused and tried to leave with their colours towards Lamia. The Evzones resisted the pursuing squadrons of chasseurs à cheval and spahis. According to these accounts 59 Greeks were killed, and 49 officers and 269 men were taken prisoner. Greek sources give varying figures for the French losses, generally seven killed. In Greece the clash was remembered as the “battle for the colours”, because the captured Evzone colours were sent to Sarrail as a trophy.

Otherwise the French met no resistance. On 13 June they took Volos and Trikala. Falls notes that the population of Thessaly, unlike that of Athens, proved distinctly Venizelist and welcomed the soldiers as liberators. Greek studies, however, mention numerous arrests of Venizelos’s opponents, pointed out by local Venizelists. On 16 June a small British detachment from the 2nd Battalion of the East Yorkshire Regiment reached Larissa, and Venel sent it further south in support of his cavalry. The British provided it, as they did the detachment at Piraeus, only as a token of Allied solidarity.

The isthmus and Piraeus

A French infantry regiment, two companies of Senegalese tirailleurs and artillery were sent to the Isthmus of Corinth. The landing passed without incident. Abbott writes that the French took up the railway tracks linking the Peloponnese with Athens. The news of this, together with word that the French fleet in the Salamis strait had been reinforced, reached Athens on 11 June and increased the unease in the city.

The landing force for Athens waited on its transports, because the British government had protested against a landing before the ultimatum was delivered. When the King agreed to leave, but the crowd in Athens still would not let him go, on 12 June French troops began to go ashore at Piraeus and took up a strong position between the port and the city. The British official history of the war at sea (Newbolt) states that about 8,000 French and 3,000 Russians landed, under the cover of the guns of Vice-Admiral de Gueydon’s squadron with the battleships Justice and Vérité. Falls mentions two French regiments and one Russian with artillery. A British detachment from the 4th Battalion of the Rifle Brigade landed at Piraeus on the afternoon of 14 June and guarded the customs house and a hill above the town.

The operation was complicated by Italy’s actions. Without warning France and Britain, Italian troops from Albania occupied Ioannina on 8 June, and the port of Preveza on 10 June. Falls writes that the situation was tense until Italy agreed to withdraw its troops as soon as the Entente forces left Athens and Thessaly. The French, meanwhile, continued to advance. According to Greek studies they had taken Lamia by 26 June, and on the morning of 27 June, the day of Venizelos’s return, the soldiers of General Charles Regnault, commander of the landing force at Piraeus, occupied the main squares of Athens.