The First World War took place just over a century ago, from 1914 - 1918.
Start with the nerve-wracking first 9 minutes of the recent block-buster movie on World War One, 1917.
The two main alliances were the Allied Powers (Britain, France and Russia) and the Central Powers (Germany, Austria-Hungary and Italy)
Explore this fascinating topic together with BBC History.
Read about the causes of the war, as well as how the war itself unfolded over the four years.
The main causes for the war were the Alliance System in Europe, which was worsened by the colonial rivalry between Britain and Germany.
Video Summaries of World War One
(NEW!) What caused the First World War here, and many more terrific animated clips on various aspects of the war on SIMPLE HISTORY.
(NEW!) Study in detail all the major events in World War One, here in EPIC HISTORY TV. You can also trace the war year by year.
(NEW!) Insane WWI facts that will shock you! Discover this and more on THE INFOGRAPHICS SHOW.
(NEW!) Archduke Franz Ferdinand's assassination started the whole war! Learn more about him and his tragic love story on KINGS AND GENERALS.
Video: Five Most Haunting Photos of WWI
Video: A Summary of WWI
Video: Simple History on the Treaty of Versailles - what the Big Three wanted (part 1 & part 2)
Video: here is a concise explanation of the terms of the Treaty of Versailles in 3 minutes
Video: an older but reliable BBC documentary, entitled Make Germany Pay (20 minutes)
Video: The Necessary War - World War One. A BBC production, rather Anglocentric but provides a reasonable overview. Includes interviews with historians such as Margaret Macmillan (60 minutes)
Video: Twenty-five interesting things you did not know about World War One.
One the most haunting poems about WWI is "In Flanders Field," written in 1915 by Lt. Col John McCrae, a Canadian doctor who fought in the battle of Ypres in the Flanders region of Belgium.
** Activate and exercise your historian's skills by examining the authentic WWI documents and sources here.