The first book of its kind to appear since the end of the Cold War, this indispensable reference provides encyclopedic coverage of communism and its impact throughout the world in the 20th century. With the opening of archives in former communist states, scholars have found new material that has expanded and sometimes altered the understanding of communism as an ideological and political force. brings this scholarship to students, teachers, and scholars in related fields. In more than 400 concise entries, the book explains what communism was, the forms it took, and the enormous role it played in world history from the Russian Revolution through the collapse of the Soviet Union and beyond.