Major World War I battles, were primarily fought on the Western Front, they characterized by extreme industrial scale  attrition, trench warfare,  massive casualties and, often, stalemate. Key battles included the Battle of Marne (1914), Verdun (1916),  Somme (1916), Passchendaele (1917), and the final Meuse-Argonne Offensive (1918), which helped end the war for once and for all.  

main battles of the great war

battles on the western front;

• Battle of the Marne (September 1914): A major Franco-British victory that halted the Germans invasion of France, ending the war's initial mobile phase and starting trench warfare.
• Battle of Verdun (February–December 1916): One of the longest and most costly battles, lasting over 300 days as Germany attempted to "bleed France white".
• Battle of the Somme (July–November 1916): A massive Allied offensive designed to relieve pressure on Verdun, resulting in over 1 million casualties, including the bloodiest day in British military history (57,000 casualties on 1 July).
• Battle of Passchendaele (Third Ypres) (July–November 1917): Known for its horrific, muddy conditions, this battle saw Allied forces fight to break German lines in Belgium for limited gain.
• Battle of Cambrai (November–December 1917): Marked the first large-scale, effective use of tanks, demonstrating a new method for breaking the trench stalemate.
• German Spring Offensive (March–July 1918): A series of rapid German attacks trying to win before the full arrival of U.S. troops, which initially succeeded but ultimately exhausted their army.
• Hundred Days Offensive (August–November 1918): The final, successful Allied offensive that broke German resistance, forced retreats, and ended the war forever

Eastern Front and Other Key Locations

• Battle of Tannenberg (August 1914): A major German victory over the Russian Second Army in East Prussia, destroying most of the Russian force.
• Gallipoli Campaign (April 1915–January 1916): A failed amphibious operation by Allied forces designed to knock the Ottoman Empire out of the war.
• Brusilov Offensive (June–September 1916): The most successful Russian offensive of the war, which severely weakened Austro-Hungarian forces.
• Battle of Jutland (May 1916): The only major naval battle of the war, where the British and German fleets fought a massive battle in the North Sea to an inconclusive result.