Wikimedia
Wikipedia: Battle of Verdun
Wikipedia provides very extensive information on the Battle of Verdun, a major action in World War I that resulted in more than 250,000 deaths.
US Army Center
U.s. Army Center of Military History: Wwi: The u.s. Army Overseas
From a book, American Military History, this chapter looks at the U.S. Army overseas in World War I, and gives a brief overview of the battles in which the Army was involved, and General Pershing's command in World War I.
Wikimedia
Wikipedia: World War I
This site from the Encyclopedia Wikipedia provides an in-depth encyclopedia article on World War I, giving information about the origins of the war, the initial outbreak, new technology introduced during the war, the Russian Revolution,...