On October 15, 1894, Alfred Dreyfus, a Jewish artillery captain attached to the French General Staff, was arrested for having betrayed his country by selling military secrets to the Germans. He was convicted of treason by military courtmartial and sentenced to life imprisonment on Devil’s Island, but over the next 12 years a small group of human rights supporters was able to clear him and identify the real traitor, and Dreyfus was pardoned. The most sensational case in French history, it pitted national security interests against individual rights, exposed the anti-Semitism that permeated France, and influenced the course of Europe as it rumbled toward the first of two world wars. This work provides a comprehensive examination of this incident for students, including a narrative historical overview, essays on major aspects of the event, lengthy biographical profiles of the key players, the text of important primary documents contemporary to the time, a timeline of the event and list of French Presidents and Ministers of War during the Affair.