This finely produced volume is the first fruit of a long-term collaboration begun between the archaeological research center Die Forschungsstelle Kaiserpfalz in Ingelheim am Rhein (Holger Grewe, director) and the legal history research center Max-Planck-Institut für europäische Rechtsgeschichte und Rechtstheorie in Frankfurt am Main (Caspar Ehlers, senior research fellow). The project entails an interdisciplinary study (i. e. archaeology, art/architectural history, history) of the Rhine-Main region as a cultural landscape where diverse cultural groups (Romans and Franks, Christians and non-Christians) encountered one another and eventually integrated their cultures during late antiquity and the early Middle Ages. Though the connection between this project and the specific subject of imperial travel routes and palace residences is never explicitly made, the archaeological sites of said palaces appear to have been a convenient locus for archaeologists, art/architectural historians, and historians to begin their expansive project.

There have been significant advances over the past two decades in archaeological research on medieval imperial palaces, which were showcased in twin exhibits: one at the Landesmuseum Mainz entitled »Die Kaiser und die Säulen ihrer Macht von Karl dem Groβen bis Friedrich Barbarossa« (9 September 2020–13 June 2021), and the other at the Archäologische Zone Kaiserpfalz in Ingelheim am Rhein entitled »Säulen der Macht. Mittelalterliche Paläste und die Reisewege der Kaiser« (9 September 2020–18 April 2021). As the latter exhibit was funded by the city of Ingelheim, its exhibit page cannot help but conclude that »die Ingelheimer Pfalz war zwar bestimmt die prächtigste, aber eben nicht die einzige Pfalz in unserer Region«. We shall appreciate the civic pride of Ingelheim’s magistrates, because it moved them to fund not only the exhibition but also the publication of this sumptuous volume.

The volume also represents an important collaboration between public and academic researchers. Holger Grewe and his staff of six Wissenschaftliche Mitarbeiter and Mitarbeiterinnen comprise the public archaeologists and art/architectural historians¹. Caspar Ehlers brings his own expertise as a research historian on medieval imperial palaces, along with professional ties to other research scholars who also have adjunct professor appointments in academic history². These adjunct appointments, and their troubling gender disparity compared with the Wissenschaftliche Mitarbeiterinnen appointments, indicate both the sad paucity of full-time, tenured professorships available for archaeologists and art/architectural historians at German universities as well as the doubly difficult path to them which still restricts representation by professional women.

Caspar Ehlers, as the only history PhD in the volume’s working group, does the heavy lifting in the introduction and two excellent opening articles, which comprise Part One. The first articulates the significance of the locations and functions of imperial Pfalzen in the Rhine-Main region from Carolingian through Staufen eras given the ambulatory nature of medieval German kingship. The second then sets the table for later studies of particular Rhine-Main palaces by establishing the locations and uses of the many Reisewege between them.

Here a persuasive case is made for the centrality of the Rhine-Main region as the essential hub for monarchs seeking to project their power throughout the vast reaches of their German kingdom. In Ehlers’ Part One material the reader finds distilled the core insights of his career studying the imperial palaces of medieval Germany. Indeed, much of these introductory chapters come from his earlier work as editor of several volumes of historical and archaeological Pfalzenforschung, which had even preceded himself at the Max-Planck Institut für europäische Rechtsgeschichte und Rechtstheorie³. He provided his own initial assessment of the state of research on imperial palaces in a 2002 volume (of which this volume is an update)⁴, having already launched his own extensive research series on German imperial palaces in 1983, a series which still remains in production⁵. In sum, one could say that Ehlers has transformed the imperial palaces from his earlier »Orte der Herrschaft« into »Säulen der Macht« for this volume. And perhaps it may can be considered an adjunct volume to his series »Die deutschen Köngispfalzen. Repertorium der Pfalzen, Königshöfe und übrigen Aufenthaltsorte der Könige im deutschen Reich des Mittelalters«.

In Part Two, seven imperial palaces enjoy a dedicated essay: two Carolingian (Ingelheim am Rhein, Frankfurt am Main) and five Staufen (Gelnhausen, Kaiserslautern, Oppenheim [which was rebuilt twice under the auspices of Rudolph of Habsburg], Seligenstadt, and Trifels bei Annweiler [this last proving to be a Reichsburg more than a Pfalz]). In comparison to Part One’s historical and historiographical contextualization, Part Two’s individual essays on specific imperial palaces often read more like archaeological field reports than historical analyses: dating and location of remains, different building periods, architectural descriptions, and probable explanations for the inevitable gaps in the surviving archaeological record.

This is particularly so in the essays on Ingelheim (Matylda Gierszweska-Noszczyńska, Katharina Peisker), Oppenheim (Christofer Herrmann), Trifels bei Annweiler (Barbara Gaertner, Ramona Kaiser, Sabine Kindel, Piotr Noszczyński) and Kaiserslautern (Holger Grewe), which consider the archaeological and architectural legacy of the palaces to the exclusion of what they can tell us about the historical functions and everyday life of imperial palaces as well as about their legacies for German history. Given that both Ehlers and Grewe state in the introduction that this interdisciplinary project was to be a study of the Rhine-Main cultural landscape from the Carolingian through the Staufen eras, it appears that disciplinary interests still diverged between history and archaeology/architectural history by publication time.

This being said, the essay on Trifels bei Annweiler highlights the use of exciting new technologies like LiDAR (Light Detection and Ranging, a.k.a. Airborne Laser Scan), GIS, and three-dimensional digital modelling. Sebastian Ristow’s essay on Frankfurt am Main at least provided a historiographical review of the seventy-year research literature published on the oft-disputed origins of that Carolingian palace. Yet every essay that covered the aesthetic and cultural record of palace architecture and decoration always held this reader’s attention. Two essays, on Gelnhausen (Katarina Papajanni), and Selingenstadt am Main (Rainer Atzbach) did cross the interdisciplinary threshold and thereby generated important insights for cultural and well as political history.

They both foregrounded the significance of these new palaces as administrative means and cultural expressions of the expansion of Staufen terra imperii across the Main River and into the Wetterau region. And Atzbach rightly notes how striking it was that Selingenstadt was the one palace without a defensive wall, so bold and confident was the Staufen presence in the Wetterau. Both Gelnhausen and Selingenstadt stimulated thriving markets and commercial communities which soon became Reichsstädte (the latter only until 1309), which suggests that some attention should have been given to the role of imperial palaces in the economic development and urbanization of their surrounding area.

Finally, this is indeed a beautifully designed and printed volume. A full 118 images appear on its 184 pages, the vast majority in bright color which provides the sort of visual learning so apropos for archaeological and architectural scholarship. Here the cultural historian and the material culture scholar can come together and dine happily. The excavation maps in the Kaiserslautern essay, however, are too small to read the textual information (they appear to have been reproduced from another source, perhaps from the exhibitions).

Any historian would be delighted to obtain such publishing features nowadays, and readers will clearly see the benefits of civic support for public history projects like this one. This volume represents an extensive effort at collaboration, from an international mix of scholars who work astride the boundaries between public and academic scholarship, to two research institutes, and one city’s celebration of its own historical roots in a medieval imperial palace. Such collaboration can only be applauded, and this volume provides plenty of evidence for the positive results that can happen when we drop our trowels and manuscripts long enough to talk with one another.