The essays in »Unterstützung bei herrscherlichem Entscheiden«, edited by Michael Grünbart, grow out of a recent conference of the same title. The various questions that animated the conference and shape these essays are important if challenging: In making political decisions, understood very broadly, how have princes drawn on experts and expert advice? How have they recognized certain domains of expertise as applicable to their immediate problems? How have they adjudicated between competing divinatory, prophetic, and predictive practices? What role does the identity of the expert play in this process, and how is that identity established and asserted? The contributions to this volume provide rich and nuanced detail into the dynamic contexts in which princes drew on expert advice.

Refreshingly, this collection avoids the courts and princes that have already received considerable attention. Many of these essays focus on the Byzantine context, with the remainder offering comparative studies, including a chapter on ancient Chinese dynasties, one on a 13^th-century Yemeni pretender to the throne, and various courts in the Latin-speaking realm. Astrology with its long tradition of providing both predictive and interpretive practices recurs throughout the essays, but other types of prognostication attract these scholars’ attention.

Benjamin Anderson’s essay points to the way that the medieval Greek context seems to have developed a particular kind of oracular image, including both public monuments and paintings in books. Both types of images served a new type of prognostication that was fundamentally different from earlier methods of augury. Book-bound oracles reassured the interpreter that irregularities in, for example, imperial succession did not threaten the continuity of the office. In this way, they served as a form of historical record that when »properly« interpreted could confirm the emperor’s rule. Anderson mentions another type of oracular image: public monuments around Constantinople. Columns in particular, came to be understood as both recalling the past and foretelling the future. The column as oracular image is an important aspect of András Kraft’s essay. Kraft shows how emperor Alexios Mourtzouphlos’ execution was linked to the prophetic interpretation of the relief on a column in the Forum of Theodosius. The crusaders reinterpreted the column’s imagery as foretelling the emperor’s execution, by being thrown from its top. Both public monuments and book-bound images were susceptible to new interpretations that were used to justify or legitimize actions.

Essays by Anne-Laurence Caudano and Paul Magdalino analyze the contours of astrology under the Komnenoi emperors. Caudano finds a preference for traditional astrological practices, e. g., nativities and elections, and a resistance to non-traditional forms of astrological practice, e. g., interrogations and political astrology. Similarly, Magdalino sees the revival of astrology at this time as a return to earlier intellectual patronage practices.

Demestrios Kyritses and Florin Leonte move beyond the forms of prognostication and, instead, draw our attention to the physical and institutional arrangement of advisors around the emperor. They give us a finely drawn picture of how circles of advisors radiated out from the emperor, proximity being a measure of perceived influence. But they are quick to point out that the nature of imperial decision-making makes it difficult if not impossible to know what influence these advisors actually had.

Matthias Heiduk’s and Hans-Christian Lehner’s chapters look beyond astrology and the Byzantine context. Heiduk relies on library catalogs to reconstruct the interests of rulers at the Staufer and the Valois courts. While there is considerable, tantalizing evidence in these catalogs, he finds it difficult to recover the non-astrological forms of prognostication. Astrology’s authority and institutional setting obscures other mantic practices. Lehner turns his attention to the ways that medieval historians recounted rulers’ decision-making practices, and what that reveals about contemporary values and practices, particularly in the liminal spaces between full Christian control and »mission space« in the East. He finds that they were most concerned with recording and transmitting proper decision-making practices related to warfare.

Other chapters try to recover complex decision-making processes of different historical figures – Michael Schimmelpfennig provides a long view of the bureaucratic and intellectual basis for decision-making in ancient China; Felix Maier offers an analysis of Emperor Julian’s process to launch his Persian expedition in 362; Klaus Herber’s essay details how Pope Nicolas I (858–867) was held up as a model of decision-making. With Petra Schmidl and Ulrike Ludwig we see once again the importance of astrology and practice that depended on astrology. Schmidl analyzes a book written by al-Ashraf ‘Umar in 13^th-century Yemen. He compiled a sort of handbook for decision-making. The contents reveal the importance of astrology and celestial phenomena in his processes. Ludwig’s essay traces the way astrology and the related practice of geomancy played an important role in the political praxis of Augustus, the elector of Saxony.

This collection of essays puts us in a stronger position to ask the next set of questions about decision-making. First is the question of the expert. In his introduction, Michael Grünbart draws attention to the role of the expert advisor and the challenges of locating that expert. In most of these essays, the expert remains conspicuously absent. Finding the expert is likely an intractable problem, one that Herbers, Kraft, and Schimmelpfennig each acknowledge. Their work along with the other essays in this volume can serve as a starting point for subsequent work that might get us closer to finding the expert. Second is the question of influence. As Kyritses pointed out, we have very little way of knowing what sort of influence the concrete decision-making practices had in shaping the final decision. Influence, in this case, is likely related to both the content of the decision-making practice and the identity of the expert advisor. How a prince decided between or evaluated the various practices available was likely a combination of content and presentation. Unfortunately, we rarely find evidence of a prince explaining exactly why a particular decision was made in a particular way. These questions do not detract from this excellent collection. They are, instead, evidence that this collection will enable us to ask more difficult questions. Scholars interested in the decision-making processes or the various ways prognosticatory practices were used at court will learn a lot from this volume.