The Battle of Verdun (1916) was the longest single battle of the First World War, lasting for more than 300 days. It represents one of the bloodiest battles of the war with over 700,000 combined casualties.
The very first global conflict to span multiple continents and oceans, World War I kicked off in July 1914 and ended in November 1918. Territory was lost and gained, empires crumbled and millions sacrificed their lives to fight for their countries.