World War I

World War I was a major conflict conducted mainly in Europe from 1914 to 1918.

Events
The war was started due to the Nemesis statue passing by Earth in 1913. (DW: Silver Nemesis)

The immortal Jack Harkness served in the war. (DW: Utopia) Tommy Brockless served in the war aswell. (TW: To the Last Man)

In 1914, the Doctor, Tobias Philby and Thomas ended up in a no man's land in France, where they learned of a German artillery build-up and warned the British army of it. (TVC: The Amateur)

In 1915, the RMS Lusitania was sunk, precipitating the United States getting involved in the war. (BFA: The Sirens of Time)

The Doctor and Susan observed a Zeppelin air raid during the war. (DW: Planet of Giants)

The War Lords kidnapped several World War I soldiers for use in their War Games. (DW: The War Games)

The Doctor claimed to have been wounded at Gallipoli. (DW: The Sea Devils)