The articles investigate dozens of cases of ethnic cleansing in the twentieth century. A number of contributors deal with ethnic cleansing in the period of World War I, in particular those episodes arising from the clash between Greece and Turkey at the end of the war. The period of World War II gave full play to the deadly policies of Stalinist Russia in the East and Hitler's Third Reich, as well as many cases which clearly spun off of these policies of ferocious ethnic cleansing. Hence, contributors deal with ethnic cleansing of Poles by Ukrainians, Romanians by Russians, Germans by Titoist Yugoslavia, and others.