The War to End All Wars: World War I by Russell Freedman

From chapters.ca:
Acclaimed for his unique ability to "find the story" in nonfiction, Newbery medalist Russell Freedman has turned his attention to the complex subject of World War I. Although World War II is widely represented in children's nonfiction and fiction, few authors have tackled WWI, perhaps because it is so complicated - and so grisly. Here Freedman tells the story of WWI in clear, economical prose, distilling the historical record into an engrossing narrative - and pulling no punches in quoting from contemporary accounts of the destructiveness and carnage of the first war to be fought with modern weapons.