1. Global Scale: World War I was a truly global conflict, involving not only European powers but also countries from around the world. The war stretched across multiple continents and oceans, making it the most widespread war the world had seen up until that point.
2. Unprecedented Scale of Destruction: The First World War was characterized by unprecedented levels of destruction and casualties. The development and widespread use of new military technologies such as machine guns, tanks, and chemical weapons caused immense loss of life and destruction on an unprecedented scale. The magnitude of the war made it stand out from previous conflicts.
3. End of an Era: World War I marked the end of the old European order and the rise of new world powers. It led to the downfall of several empires, including the Austro-Hungarian Empire and the Ottoman Empire. The war also sowed the seeds for significant geopolitical shifts and led to the reshaping of the global power dynamics in the aftermath.
4. Lasting Legacy: The war left a lasting impact on the world. It resulted in the creation of new international organizations, notably the League of Nations, aimed at promoting peace and preventing future conflicts. The war also led to significant social, economic, and cultural changes within countries, shaping the world we know today.
Over time, as other wars occurred, the term 'World War' became more widely used to distinguish the First World War from subsequent global conflicts. Nonetheless, the title "Great War" persists as a reminder of the immense scale and profound significance of the First World War.