Between 1945 and 1950, approximately 130,000 Germans were interned in the Soviet zone of occupied Germany, including in former Nazi concentration camps. One third of detainees died, prompting comparisons with Nazi terror. But what about the western zones, where the Americans, British, and French also detained hundreds of thousands of Germans without trial? This first in-depth study compares internment by all four occupying powers, asking who was interned, how they were treated, and when and why they were arrested and released. It confirms the incomparably appalling conditions and death rates in the Soviet camps but identifies similarities in other respects. Andrew H. Beattie argues that internment everywhere was an inherently extrajudicial measure with punitive and preventative dimensions that aimed to eradicate Nazism and create a new Germany. By recognising its true nature and extent, he suggests that denazification was more severe and coercive but also more differentiated and complex than previously thought.