The initial objective of the Allies was to bring assistance to the Serbs who were retreating before the Austro-German and Bulgarian invasion. This assistance was to have taken the form of an advance up the Vardar Valley towards Uskub or towards Monastir. As soon as the troops were landed at Salonica they were immediately pushed forward towards the front, the British to the east of the Vardar and the French to the west. On October 20th the French reached Krivolak on the Vardar and occupied the whole peninsula formed by that river and the Cerna, while the British were to the north of lake of Doiran, on the Kosturino Pass on the Beles Mountains, whence it is possible to descend into Bulgaria. The Serbs were being driven ever further south, but a detachment of their army was holding Monastir. If they had followed the advice of the Allies and had retreated towards them, perhaps a part of the army might have been saved; but, attracted by the mirage of an outlet on the Adriatic, or for some other motive, they insisted on deviating towards the west, thus undertaking that retreat across Albania which was to prove one of the most terrible tragedies of the whole war. Before the invasion the Serbian Army comprised 400,000 men, when it reached Albania it was reduced to 150,000, with some tens of thousands of Austrian prisoners; the rest had died of hunger and suffering. This miserable remnant was saved by the assistance of the Allies, and particularly of the Italians, as we shall see further on. The retreat through Albania rendered the situation of the Anglo-French on the middle Vardar untenable. When the French learnt that the Bulgarians had occupied the Babuna Pass between Veles and Monastir at the beginning of November, they tried to break the enemy front on the left bank of the Cerna in the hope of reaching the Serbs to the north-west of that pass. For fifteen days (November 5–19th) a fierce struggle went on between the French and the Bulgarians, in which our Allies showed all their admirable military qualities. The Bulgarians counter-attacked on the Cerna and were repulsed with heavy losses, but as the bulk of the Serbian Army had retreated towards Albania and the French had been unable to capture the dominating position of Mount Arkhangel (west of Gradsko on the Vardar), the offensive passed definitely to the Bulgarians. On the 2nd, General Sarrail ordered a general retreat from Krivolak on Salonica. Even this operation was anything but easy. It was necessary to withdraw 3 divisions (the 122nd had been recently added to the 156th and 57th) and an enormous quantity of material along the Vardar Valley over a single-track railway and without decent carriage roads, in a season when the rains converted the whole country into a vast muddy swamp. It must be admitted that General Sarrail conducted this retreat in good order. The Bulgarians were attacking from the north towards Krivolak and from the west on