ABSTRACT This study examines officer losses during the first three months of Operation Barbarossa. It uses original, never-published German officer casualty data extracted and statistically analyzed from 13 by-name reports prepared by the Army Group Center Adjutant for Officer Personnel (IIa) during the summer of 1941. The list, comprising 7,644 names, proposes a periodization of the first phase of Operation Barbarossa in the Army Group Center zone of operations and presents an innovative perspective that uses the rise and fall of officer casualties as a one-of-a-kind measure of combat intensity. In other words, periods of differing casualty rates are seen as discrete operational phases when equated to neighboring intervals. To make the losses comparable across time, the article proposes the concept of division-days, which, in a manner similar to man-hours, records effective activity of these units in daily intervals. The casualty rate compared to total number of division-days is a measure of intensity. The analysis indicates that although there are three operational periods, two later phases see higher odds for officer losses, indicating intensified combat. In addition, the article considers several under-studied aspects of operational military history. First, it analyzes the distribution of casualties across divisions as a function of their posture (attack, defense, movement, reserve). The article further reveals that battle posture does not always follow the precept that ‘movement is the best defense’. In fact, overall analysis shows that units maneuvering (attack and move) were more likely to lose officers than those stationary (defend and reserve). Overall, the article is a first attempt to judge the nature and intensity of Barbarossa as a function of complex, over-time data, broken down by types of unit and posture, revealing how dear the officer casualty toll was for the Germans, setting the tone for a long and ultimately unwinnable war.