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1915 The multiplication of fronts

This map is part of a series of 20 animated maps showing the history of The first World War, 1914-1918.

The decisive battle did not take place, and the conflict promised to last longer than the general staffs had anticipated. In the course of the year 1915, the entry of new belligerents into war led to a multiplication of fronts.

The first to become involved along with the Central Powers was the Ottoman Empire.

Military operations were soon launched in the Caucasus and the Arab provinces.

At the beginning of 1915, French and British leaders decided on an intervention in the Bosporus, with the objective, among others, of re-establishing links with the Russian ally.

The naval operation, and the subsequent landing of the troops in the Dardanelles, ended in bitter defeat.

In May, after long hesitation, Italy abandoned its neutrality and sided with the Allies.

With the objective of taking Trieste, the Italian army launched several offensives on the Isonzo front, with the loss of many lives. The territorial gains were limited, however, in view of the solid Austro‑Hungarian lines of defence.

The German general staff now gave priority to the eastern front, and sought victory over Russia, intending to redeploy its troops later to the French front.

In May, the German and Austro‑Hungarian armies launched a series of victorious offensives in Lithuania, Poland and Galicia and, by mid-September, the front had shifted to a line running from Riga to the Romanian border. The Russian army backed off and suffered substantial losses, but, contrary to the objective of the German general staff, had not been put out of action.

On the western front, the French infantry had multiplied its attacks since winter. These operations resulted in considerable losses for insignificant territorial gains. But, nevertheless, Joffre continued his attempts to break through the German front; for each effort, he employed greater numbers of men and equipment.

The strongest of these offensives was launched in Champagne on 25 September. It was preceded by 3 days of devastating artillery strikes and backed up by a second Franco‑British operation in Artois.

Once again, breaches in the German front lines were quickly repaired without a decisive victory.

In the autumn of 1915, Bulgaria also entered the war and participated in the offensive launched by the German and Austro‑Hungarian troops against Serbia.

The landing of a French contingent at Salonica to support its ally was unable to avert disaster for the Serbian army.