World War I, occurring between 1914 and 1918, was a global conflict centered in Europe.
It involved the Allied powers (primarily France, the United Kingdom, Russia, and later the United States) against the Central powers (Germany, Austria-Hungary, the Ottoman Empire).
The assassination of Archduke Franz Ferdinand of Austria triggered pre-existing tensions.
Trenches dominated much of the Western Front, with deadly battles. The war witnessed the use of new technologies such as chemical and aerial weapons. The conflict concluded
