In 1915, the Great War evolved into a global struggle of unprecedented, industrialized brutality.

History · Published 29 September 2026 Swipe more like this →

In short: The year 1915 transformed World War I from a war of movement into a grinding, technological stalemate. From the first use of chemical weapons and strategic air raids to the sinking of the Lusitania and the Armenian Genocide, the conflict expanded across land, sea, and air with devastating consequences.

The year began with tactical shifts that signaled the war's escalating lethality. On the Eastern Front, Field Marshal Paul von Hindenburg secured a victory at the Second Battle of Masurian Lakes, though Russia countered by capturing 100,000 Austro-Hungarian prisoners at Przemyśl. Meanwhile, the Western Front saw the introduction of chemical warfare during a German attack at Ypres, and the British offensive at Neuve Chapelle underscored the failure of traditional tactics against entrenched positions. By mid-year, Germany achieved air superiority through the deployment of the Fokker Eindecker, a monoplane featuring a forward-firing machine-gun.

Naval warfare became increasingly ruthless as Germany declared an Exclusion Zone around the British Isles, initiating unrestricted submarine warfare. This policy led to the sinking of the RMS Lusitania, which resulted in 1,198 civilian deaths, including 128 Americans. The incident sparked international outrage, forcing Germany to temporarily suspend attacks on passenger vessels. Simultaneously, the Allied campaign at the Dardanelles turned into a disaster; despite the arrival of battleships and the landing of ANZAC troops at Gallipoli, Turkish shore-forts and sea mines inflicted heavy losses, pinning down Allied forces in a prolonged, bloody stalemate.

The human cost of the year was staggering. In April, the Ottoman Empire began the systematic arrest, deportation, and execution of ethnic Armenians. While the Turkish government disputes the characterization of these events as genocide, most historians and many nations classify them as the Armenian Genocide, citing a death toll between 1 and 1.5 million. As the year closed, the Great Autumn Offensive—comprising the Third Battle of Artois, the Second Battle of Champagne, and the Battle of Loos—failed to break the deadlock on the Western Front, resulting in massive casualties for the British and French forces while yielding almost no strategic gains.

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