Marked by two world wars, the Holocaust, and a host of violent conflicts, the twentieth century has been the most explosive and destructive in human history. As we enter the twenty-first century, it is vital that we understand what went wrong in the preceding 100 years. This volume covers the landmark events from 1900 through the Second World War: the Russo-Japanese War, the global repercussions of World War I, the Russian Revolution, the Great Depression, Mussolini's fascism, Hitler's nazism, Stalin's socialism, the Spanish Civil War, the China of Mao and Chiang Kai-shek, World War II, the development of the atomic bomb, and more. In addition, Kantowicz probes behind the events themselves, examining their source in the five terrible "isms" of the twentieth century - anarchism, socialism, imperialism, nationalism, and ethnocentrism. Proving compelling often disconcerting reading, this book helps make sense of what is happening in the world today by considering important lessons from our recent past.