AT THE END of World War II, between twelve and fourteen million people, ethnic Germans, were forcibly expelled from Eastern Europe, or, if they had already fled, were prevented from going back to their homes. Many of them were simply bundled on to cattle trucks of the sort previously used to take Europe’s Jews to their fate in the gas chambers of Auschwitz and Treblinka, and sent westward to Germany without food, water, or adequate winter clothing. Others were detained in appalling conditions in concentration camps for weeks, suffering from disease, starvation, and maltreatment, before they were brutally pushed out to the west. Long lines trudged towards Germany, with the weak succumbing to hypothermia and malnutrition. Altogether probably half a million and perhaps as many as a million perished in what was the largest action of what later came to be known as “ethnic cleansing” in history.

This massive act of expulsion and forced migration is still largely unknown outside the countries most closely affected by it. The story appears in standard histories of Germany and Europe in the twentieth century as little more than a footnote. Calling it to public attention questions the widespread popular understanding of World War II as a wholly good fight by the Allies against the evil of Nazism and German aggression. Unfortunately, history is seldom as simple as that. Until recently, few historians troubled to investigate the expulsions in any depth, and what writing there was on the topic was bedeviled by one-sided narratives of German suffering or Polish or Czech self-justification. But since the fall of Communism and the opening of the archives in these countries, serious and reasonably objective historical research by a new generation of younger historians less affected than their predecessors by national or ethnic prejudice has begun to appear. R. M. Douglas’s Orderly and Humane: The Expulsion of the Germans after the Second World War draws on this recent work and incorporates archival research in Germany, Poland, and the Czech Republic as well as the files of the International Committee of the Red Cross, the UN Relief and Rehabilitation Administration, and the records of the British and American governments. It is a major achievement: for the first time it puts the whole subject onto a scholarly footing.

The expulsions, as Douglas points out, were no mere act of mass revenge carried out by peoples of Eastern Europe who had suffered under the Nazi jackboot. On the contrary, they were ordered by the Allies, and planned long before the war came to an end. The mistreatment of ethnic minorities before and during World War I in the Habsburg and Ottoman empires had led not just to a determination in the international community to guarantee their rights, but more importantly to a decision to cut through the problem by creating unitary national states. As the Tsarist Empire, itself no mean oppressor of minorities such as the Poles, fell apart, the Western Allies found meaning in the continuing conflict by declaring one of its objectives to be the realization of the democratic principle of “national self-determination.”

At the Paris Peace Conference in 1919, however, the seemingly simple and obvious idea that every nation should have the democratic right to elect its own government foundered on the intractable realities of centuries-old patterns of ethnic and religious diversity in East-Central Europe, and ran up against the requirements of security and viability for the new states created out of the wreckage of the old. Almost every one of them contained substantial national minorities. Naturally the peacemakers did their best to incorporate guarantees of minority rights into the settlement, but these proved impossible to enforce.

A case in point was the German-speaking minority in Czechoslovakia—three million people who made up nearly a quarter of the new Republic’s total population. The historic borders of the Kingdom of Bohemia included these people, and without them the new state would have lacked vital industries and defensible borders. Czech nationalism, already very passionate before 1914, was too strong a force to admit the German-speaking minority to equal rights, though liberal Czech politicians did their best to limit discrimination. And when Eduard Beneš took over as president in 1935, a new, harder note of Czech nationalism was heard, sparking a new radicalism among the German minority, who soon flocked to support the Sudeten German Party of Konrad Henlein. By 1937 this had become a Nazi front, dedicated to subverting the integrity of the Republic and opening it to German invasion and occupation.