The extent to which the actions of superior courts were controlled in the early-modern period, and the ways in which any control was exercised, are central to an understanding of the development of the idea of the Rule of Law and of the constitutional framework of the emergent nation states of the time. This collection of essays, concentrating on Germany, Scotland and Spain (Castille, Aragon) with solitary essays on England and Sweden, is intended as a preliminary to a wider study of European, and European colonial, systems, and it will only be with the full study that we will be able to reach general conclusions. It will, too, make considerable demands on those leading the project to pull together the disparate materials from a range of very different regions.

Most of the courts dealt with in this collection were set up by, or supplemented by, instruments which laid down their powers and procedures, in some cases accompanied by mechanisms to ensure that the court's ordinances were being observed. Where procedures were set up – Aragon is perhaps the best example in this volume – they could simply be followed; though whether the oversight extended to matters of substance as well as matters of procedural propriety might vary from court to court. Where there were no such procedures, as with the Scottish College of Justice, the court might none the less be subject to political oversight by indirect means, most obviously through monarchical control over the court's membership. Yet even in the absence of formal or constitutional mechanisms, as John Ford's paper on early-modern Scotland shows, kings might intervene in the legal process. It might have been the experience of James VI in Scotland that precipitated his anger when, as James I of England after the union of the crowns in 1603, the English judges denied his power to determine cases in England.

Of the systems considered in this volume, England is the clear outlier. Its superior courts, the King's Bench and Common Pleas, were not created by legislative action and so were not governed by any formal procedural norms. Nor were the so-called prerogative courts which grew in the sixteenth century, the control of which became a major feature of the constitutional controversies of the 1590s and after. Ulrike Mässig's paper concentrates on the use of the prerogative writs, especially prohibition, to set boundaries on the jurisdiction of these courts: rightly so, perhaps, though the focus on these means that insufficient attention is paid to informal intervention by monarchs before the well-studied examples of the first decade of the reign of James VI and I. It does need to be stressed, though, that prohibition was primarily used by individuals trying to prevent cases brought by other individuals being heard in what they argued were inappropriate courts and only very rarely by the monarch; and their legitimacy was determined by the common law courts themselves (the same is true of habeas corpus, if it is correct to think of that as a prerogative writ). It was not, therefore, a mechanism for controlling the supreme court(s) in England, but rather a mechanism whereby the judges of those courts could prevent what might have become a rival structure of courts from developing. We may suspect that it was in the thirteenth century, too early in truth for this volume, that royal control was at its height, though the scope of the writ ne rege inconsulto before the constitutional struggles of the seventeenth century would be well worth further investigation.