In compiling Royal and Urban Gunpowder Weapons in Late Medieval England, Dan Spencer had a clear objective: to produce a comprehensive study of early gunpowder weapons in England, from their first use by English forces to the end of the reign of Henry VII. In short, he has succeeded. He traces the development of these weapons through a commendable examination of the surviving records. Looking beyond the evolution of this technology and the way that guns were employed, Spencer also investigates the changing role of the men most closely associated with these weapons and the varying degrees of attention dedicated to them by different monarchs and urban communities through the course of the period.

Throughout, Spencer employs a clear framework: the available sources are introduced, along with a short discussion of their strengths and limitations; the available evidence is examined, typically chronologically; a succinct conclusion then highlights the points and trends Spencer believes are most significant. This framework is applied to each chapter, as well as the book as a whole. This not only allows each chapter to stand alone, but also helps to make the work manageable for readers with little previous knowledge of the subject or context. This accessibility, however, has in no way compromised the depth of Spencer's research. While existing scholarship has been addressed and incorporated where pertinent, most of the information that forms the substance of this study has been drawn from administrative and financial records, supplemented in places with evidence from narrative accounts.

Spencer's introduction sets out a clear overview of the study to follow and provides a succinct survey of the general historiography. The first chapter details the use of gunpowder weapons by English monarchs on campaign, revealing how the greater use of gunpowder weapons clearly corresponded with the reigns of certain figures and the demands of particular campaigns and military threats. The second chapter then provides a more detailed look at three campaigns, revealing an apparent shift in the types of guns that were used between 1430 and the end of the fifteenth century. Chapter 3 examines the practice of arming royal ships. The next two chapters take a closer look at the records relating to the garrison of Calais and those of royal castles. This is complemented by the following chapters, which investigate the acquisition and employment of guns by urban communities, with a complete chapter devoted to Southampton, for which there are exceptionally detailed, if still incomplete, records. In chapter 8, many of the observations and conclusions drawn elsewhere, along with a few new ones, are brought together to highlight particular trends. Throughout the book, charts and graphs are employed with great effect, and ten appendices collate data relating to gun types, weights, and prices, and detail certain inventory and account records.

Among the conclusions of this study, Spencer points to the predictable influence of the political context when viewing investment patterns, in terms of both acquiring guns for campaigns as well as improving urban defenses at times of heightened military threat. He also points to the changing nature and increasing importance of gunpowder weapons, arguing this is evident in the greater diversity of guns from the mid-fifteenth century, as well as the increasing use of individual horse-drawn gun carriages, which made these weapons more mobile and better suited to the battlefield. He also highlights the different relationships that the rulers of England and the Low Countries had with the urban communities of their realms, and how this influenced the commissioning and requisitioning of guns. Additionally, he points to the lack of uniformity with which English towns appear to have adopted gunpowder weapons. At every turn, the types of guns, ammunition, gunpowder, and materials associated with the repair and transportation of these weapons is diligently quantified. Attention is also devoted to the mentions of “gunners” and the changing roles of these men.

In any study of medieval artillery, whether gunpowder weapons or earlier mechanical engines, terminology poses a challenge. Although many sources use a strictly defined set of terms, determining the degree of standardization among even the most diligent at any given time, let alone across an extended period, is quite difficult. Adding to this challenge is the use of more general terms by others, who might even use these interchangeably. Spencer wisely avoids trudging too deeply into this quagmire, instead asserting that the increasing number of terms used from the second half of the fifteenth century reflects the increasing technological diversity, a conclusion substantiated by the tables found in the appendices.

Spencer's final remarks are in support of the growing notion that, when it came to gunpowder weaponry, England was not technologically backward at this time. When considering the degree to which weapons and even the practice of war had changed between the start and end of the fifteenth century, he feels justified in classifying this as a military revolution. Regardless of how one defines this concept, Spencer has produced a clear, comprehensive, and detailed study that will no doubt prove influential in encouraging the further examination of these weapons and their use.