From 1309 to 1417, the popes resided not in Rome, but in the small Provençal town of Avignon. It was Clement v who first decided to settle the papacy here, but the choice to make Avignon a more permanent abode was confirmed by John xxii and his successor, Benedict xii, who was also the first to transform Avignon's former episcopal palace into the mighty fortress that visitors see today. The Avignon period was instrumental in the professionalisation and centralisation of the papal administration. Throughout their pontificates, the Avignon popes worked hard to enable the return of the curia to Rome. However, the political situation in Italy, especially the ongoing war with cities such as Milan and Florence, made this virtually impossible. Shortly after Pope Gregory xi did return to Rome, in 1378, a schism ensued, prolonging Avignon's papal role by making it the seat of one of the two (and sometimes three) competing Roman pontiffs until the schism was finally ended in 1417.

For a long time, the only accessible one-volume monographs on this period were Guillaume Mollat, Les Papes d'Avignon (1912, trans. into English in 1963) and Yves Renouard, La Papauté à Avignon (1954, trans. into English in 1970). Since then, major research has contributed to our understanding of this period. Bernard Guillemain's La Cour Pontificale d'Avignon (1962) studied the inner workings of the papal court; works by David Flood and David Burr focused on the interactions of the Franciscan order with the Avignon popes; and some popes have been the subjects of full biographies, such as Clement v (Sophia Menache, 1998) and Clement vi (Diana Wood, 1989). This makes Rollo-Koster's one-volume monograph on the history of the Avignonese papacy a welcome addition; there are few one-volume overviews that incorporate the most recent bibliographical developments.

Four of the six chapters narrate the story of the Avignon popes, mainly from a political point of view. The first chapter describes the political events that led to the papacy being established in Avignon in the first place. Rollo-Koster demonstrates that the city was not originally intended to become a seat of papal government; specific political machinations prevented the popes from taking up residence in Rome, and by the time of John xxii, necessity was made into a virtue. John's papacy was among the most controversial in the fourteenth century, leaving his successor Benedict xii to try to repair the damage to the reputation of the papacy. The second chapter is largely dedicated to the pontificate of Clement vi, and highlights especially the damage that the free companies (the independent mercenary armies that increasingly determined the face of late medieval warfare) did in southern France in the wake of the Hundred Years’ War. Chapter iii, ‘Returning to Rome’, deals with the pontificates of Urban v and Gregory xi, and their political negotiations with Florence on the papacy's safe return to Rome. The next two chapters interrupt the political narrative. Chapter iv explains the workings of the papal administration. Chapter v, ‘The capital and its population’, the most valuable and well researched chapter, offers a description of the town and the social consequences of the papal court for town life, and presents a sociological analysis of how Avignon transformed from a sleepy provincial town to a vibrant centre of church administration. The final chapter deals with the Avignon papacy at the time of the schism, detailing especially the economic and political position of Florentine merchants at the time of the schism.

Despite its obvious merits, some flaws detract from the general usefulness of this work. Most of these could have been prevented by better editing. For example, people or events that are mentioned in the text are often not explained until pages later, leaving the reader wondering whether he or she missed something at the first mention. One example may suffice here. The first time the so-called War of the Otto Santi is mentioned in the book is on p. 131, in a casual way that seems to suggest it was mentioned earlier: ‘The climax of the Otto Santi war led to a schism in the Church and the Chiompi revolt in Florence, both erupting in 1378.’ However, a detailed explanation of what this war was has to wait until p. 133, when it is mentioned that there was ‘a new crisis, the outbreak of the “War of the Eight Saints” (in Italian, Otto Santi, 1375–1378)’. Only on p. 136 do we find out who exactly these ‘Eight Saints’ were, and why they gave their name to this war. Sometimes the narrative is inconsistent. On p. 167, we are first informed that the name for the papal court of audience, the ‘Rota’, is derived from the ‘circular arrangement of its benches in the meeting room’. One paragraph later, we hear that the auditors sat on ‘a round, padded bench, hence the name of rota (wheel)’. Quotations from sources are often inserted into the narrative without regard to the syntax of the sentence, as in novice undergraduate writing (p. 256: ‘Merchants’ letters are blunt, “regarding what you are telling me, concerning your intentions to deal with messires d'Aigrefeuille and Naples [both cardinals] in order to be spared by the pope. … It seems to me that 300 to 400 florins or more would be good”.’). And finally, the narrative is sometimes marred by platitudes (the sources ‘clearly gauged the failure of institutional Catholicism in quite remarkable terms for a period that is often characterised by pious submission to authority’ [p. 255]), or by minor mistakes and chronological oddities. The reader might, for instance, wonder if Cola di Rienzo needed prophetic gifts in order to predict ‘the rise of a new saint, Francis of Assisi’, more than a hundred years after this saint's death (p. 75), or why a priest was called to hear the confession of a man who had committed suicide several days earlier (p. 259).

The blurb on the back cover of this book calls it a work of historical revisionism, and praises it as ‘elegant and readable’. Both claims are overstated. However, in giving a concise and accessible overview of the history of the Avignon papacy, this work has merit even without these superlatives. One wishes, however, that it had been properly copy-edited before being sent to the press.