Two experienced authors, assisted by two historians with skills in digital history (Julien Alerini and Stéphane Lamassé), have produced a sizeable longue durée examination of princely encounters. Many of the travels and meetings mentioned in this book have been previously described, and the story of the development of modern diplomacy has frequently been recounted. However, there was no synthesis for this period along the lines of Johannes Paulmann’s Pomp und Politik which deals with royal encounters between the end of the ancien regime and the First World War. This initiative is therefore a welcome addition.

Comment la confiance vient aux princes opens with a first part outlining the project as a whole: a chapter on the »état de la question« followed by a chapter outlining the approach and defining the main protagonists. This groundwork is then expanded in a second part that describes various categories of princely travellers and modes of travel, including incognito, before moving on to the challenges the travellers faced, such as storms, brigands, and treason. This introductory section provides the framework for three subsequent parts exploring specific themes in greater depth. The third part discusses the encounter as a »problem«, with a chapter on captivity, poisoning, and the strategies used to avoid these and other predicaments; it also alerts the reader to the difficulties of linguistic and religious diversity, with their attendant intercultural misunderstandings. The fourth part outlines the central thesis of the book’s title »building trust«, and examines the growth of systems of hospitality and ceremonial regulations. The fifth and final part considers the purpose or »utilité« of the meetings, sketching among other things marriage alliances, peace talks, and investitures. The book concludes with a final chapter discussing the surveillance of royal guests; it introduces a new theme, but as a consequence fails to offer a coherent wrap-up of the argument of the book as a whole.

The division of labour between the two main authors is hinted at in the »remerciements«, which refer to linguistic expertise, sources and literature. There is no explanation of the writing process, so we must assume that the chapters were written jointly throughout. The two assistants have worked on the »outil informatique«, assembling travel data from texts available online and transforming them into maps.

Statistics are a concern throughout the book, but are mostly treated in passing. On p. 57 the authors note that they included 3344 »entrevues« between 1494 and 1788 in their examination, 1003 for the sixteenth century, 1346 for the seventeenth century, and 995 for the eighteenth century. More specific themes are related to the data set: numbers, percentages, and tables are scattered throughout the book, e.g. on pp. 94, 109, 118, 129, 189, 297, 435–436. Thirteen maps are provided in a separate section, showing the cities and regions most frequently visited, by certain princes and over time.

The challenge facing the authors was to make sense of the abundant material on royal encounters, to uncover trends, and to chart the changing characteristics of these encounters over three centuries. Some results appear quickly, in the book’s title and in the first two parts: travel became safer, yet sovereign princes no longer travelled so often, leaving this to their diplomats, family members, and high nobles. A system arose to accommodate not only royal travellers and their encounters, but more often arranged the meeting of royals through the intervention of their personal representatives. The nature of royal travel shifted, with princelings and lesser royals visiting the great courts of Europe, and leading royals themselves travelling mostly in their younger years and incognito. The patterns sketched here do not come as a surprise; they can be found in the literature. Extending the discussion to the institutions related to permanent diplomacy, to the royal court and ceremony, and to language, the authors tread on familiar ground. These matters have been dealt with in detail in earlier works and this re-examination does little to change or nuance the consensus.

The ambition of the book to create an »anthropology« of royal encounters by bringing together many cases in a longue durée approach should be applauded: the idea is excellent. The results, however, are somewhat disappointing: no consistent and novel interpretation emerged from the attempt to systematically subject subsequent royal encounters to arithmetic. Moreover, this is not where the authors invest most of their intellectual energy. Their priority seems to reside in relating an impressive number of particular stories. These at times lead to important isolated insights: it is indisputable that the authors have a sound grasp of most events and persons they are describing. Overall, however, the book's structure and the authors’ techniques of joint writing have resulted in an overabundance of examples, including considerable repetition. It is difficult to find a sustained and novel argument beyond the relatively familiar conclusions hinted at in the opening chapters. The authors chose not to present their statistics in one coherent section with its own conclusions and queries; neither did they choose to add a more detailed and analytical examination of a selection of key examples. The book moves rapidly from theme to theme, by connecting statements to a sequence of brief examples, without much background or analysis. The ambition of this book is timely and important, the authors are acknowledged specialists in their field, but their project did not quite match the positive expectations of this reader.