This is the authoritative work on the causes of World War One. The author, Sidney Bradshaw Fay (1876-1967), was an American historian. He was Professor of History at Dartmouth College (1902-14), Smith College (1914-29), and Harvard University (1929-46). This is a book on the causes of the war, not on the war itself. Sidney Fay researches a different conclusion than almost every other researcher on the Causes of the War. Whereas others state that the War was the fault of Germany, who attacked France through Belgium on August 4, 1914, Sidney Fay asserts that Germany was forced to attack because of the circumstances it faced at the time. Sidney Fay says that Austria, Serbia, and Russia were primarily to blame for the war. Few agree with him, but on one point, all authorities agree. At the beginning, all sides believed that the war would be swift and successful. None of the countries had any idea that the war would last four years with 15 million people killed. This book is divided into two volumes. Volume One is "Before Sarajevo". Volume Two is "After Sarajevo". By "Before Sarajevo", it is meant before the assassination in Sarajevo on 28 June 1914 of Archduke Franz Ferdinand of Austria, the heir to the throne of Austria-Hungary.