The Allied invasion of Normandy on June 6, 1944, marked a critical turning point in the European theater of World War II. The massive landing on France's coast had been meticulously planned for three years, and the Allies anticipated a quick and decisive defeat of the German forces. Many of the planners were surprised, however, by the length of time it ultimately took to defeat the Germans.

While much has been written about D-day, very little has been written about the crucial period from August to September, immediately after the invasion. In Ruckzug, Joachim Ludewig draws on...