The first half of the course presents some of the major diplomatic (and sometimes military) confrontations of the twentieth century, beginning with the First Balkan War, including the breakdowns of the late 1930s and progressing through the end of the Cold War. The second half introduces the history of Ukraine and closes with a case study of the Russian invasion of Ukraine’s south and east as the end of the post-cold war order. In both parts emphasis is placed upon a close reading of primary documents and upon the reconstruction of possible alternatives.