Following the end of World War II the U.S. Army Map Service distributed maps captured from the German military to research libraries across the United States, where they have remained largely hidden collections. One focus of the University of California Berkeley's German World War II captured maps digitization project has been the creation of detailed metadata for the German military map series. Data-rich catalog records with information about source maps and the need to do authority work for related corporate bodies provided entry points for exploring issues of provenance. The topographic map series that make up the bulk of this collection reflect the fragmentary nature of German cartographic history, with varying contributing corporate bodies, diverse source material, and a range of sophistication and technique. All of these characteristics evolved between 1936 and 1945 when the Nazi regime ramped up production of military maps. The authors make the case that it is worth the time and effort for libraries to invest in creating rich bibliographic descriptions for these map series.