At the time, it was known as the "war to end all wars", but the First World War, sometimes also referred to as the Great War, was far from that, for it was followed 20 years later by the Second World War, and there have been many major and minor conflicts around the world ever since. Although World War I was a global conflict, involving all the great powers, it was centered on Europe. The combatants formed two opposing alliances: the Allies (originally...