The first world war embarked a new era in technological warfare.
World War I, originally referred to as The Great War, was a conflict fought in Europe on Earth during the early 20th century. It involved such world powers as Germany, France, Great Britain and the United States.
In describing the carnage of Earth's first three world wars, Spock noted that 6 million died in this war. (TOS: "Bread and Circuses")
- The original script for "The City on the Edge of Forever" featured a World War I veteran; however, this backstory was dropped from the character.
- Spock's figure of 6 million deaths falls short of the 16 million casualties of World War I, but may be a reference to 7 million civilian deaths or the number of deaths as a result of "despotism".