The significant global conflict that included battles such as the Somme and Verdun was World War I, which lasted from 1914 to 1918. These battles exemplified the brutal trench warfare and high casualty rates characterizing the conflict. The Battle of Verdun, fought in 1916, became one of the longest and deadliest engagements, symbolizing French determination. The Battle of the Somme, also in 1916, intended to relieve pressure on Verdun while causing significant losses to the German army and showcasing the horrific conditions soldiers faced. World War I reshaped national boundaries, economies, and political systems, ultimately leading to World War II.