1915 was characterised by deadlock and a widening of the 'Great War for Civilization' as more countries were drawn in and the combatants looked for ways of bringing the fighting to a swift conclusion.
This was typified by the ill-fated allied landings in Turkey and the entry of Italy into the war.
1915 was to see warfare take on a new dimension with the bombing of British cities by Zeppelin airships. Germany also began U-Boat attacks on neutral shipping, a policy that would contribute to the United States entering the war.
Gas was also used for the first time. The Germans utilised it with limited success against Russian forces at Bolimov but, at the Second battle of Ypres, the full devastating effects of gas became clear with severe losses on both British and German sides.
Drawn in much against their will, the Italians faced awful hardships too as the twelve battles along the Isonzo River, in present day Slovenia, ended in stalemate or disaster.