Diplomatics as a discipline begins in the seventeenth century with an argument between a Jesuit and a Benedictine monk about the authenticity of charters. The Benedictine’s seminal treatise De Re Diplomatica gave the discipline an identity, the core of which is preserved in treatises on ‘pure’ Diplomatics, and also specifically on papal Diplomatics, up to the present day. The discipline’s boundaries did not remain static, however, and already in the eighteenth century a tradition of applying Diplomatics to substantive historical problems had begun. After World War II Heinrich Fichtenau defined the contours of applied Diplomatics.

The papacy managed to meet the mushrooming demand for its documents. A new genre of documents appeared, ‘letters of grace’, granting special privileges. Demand for benefices was one major category. Only a small proportion of papal registers were registered, and two or more people might receive the same grant, so the curia developed a system of ranked formulae to see which letter had priority. Another genre met the demand for papal justice: ‘letters of justice’. These appointed judges delegate in the localities. A remarkable institution called the Audientia litterarum contradictarum made the system functional. Behind all this there was no proper bureaucracy with division between home and work, salaries and line managers. Slightly more like a bureaucracy was the Apostolic Penitentiary, which dealt with absolutions from excommunication and dispensations. In the fourteenth century, with the papacy based in Avignon, record keeping was less random and rules to regulate the otherwise unbureaucratic administration were formulated for both Penitentiary and Chancery. High level letters were handled separately from the quantitatively enormous routine business. The Schism that started in 1378, shortly after the papacy returned to Rome, marked a sharp break.

While Late Antique decretals were being transmitted to new generations, popes corresponded with kings and emperors, by the mid-to-late eighth century at times in surprisingly faulty Latin, and a new genre of papal document appeared alongside them, solemn privileges, written on papyrus, two or three meters long, mostly for monasteries. Not much thought was required to compose them, as beneficiaries brought drafts of the substantive part and a formulary supplied the top and the tail. What exactly these privileges granted is a matter of debate. They were written in a script descended from late Roman cursive and hard to read. This was probably an advantage. The archaic script concealed bad Latin. And the appearance would have inspired awe. In the eleventh century the late Roman script and the long papyrus format were abandoned, to be replaced by new devices to make the document impressive. What exactly they were granting to monasteries became clearer in the twelfth century.

Some continuities run through the long period from the late Roman empire to the Counter Reformation. An archive existed well before the empire in the West collapsed. Throughout the period papal government was largely demand driven. To settle disputes in far-away localities of which the popes knew little, they delegated authority to men on the spot who were not paid for their services. The papacy lacked the resources to fund a ‘Weberian’ bureaucracy, but was adept at devising rules to run systems that circumvented its own shortcomings, and thus it was able to meet the expanding demand for its services.

‘Governing the world by writing’ is the intriguing title of a recent book about the late antique and medieval papacy. The subtitle reveals it to be about relations with Dalmatia only,1 but the concept is applicable to the present work, which tries to explain how the papacy governed the world, in its religious aspects at least, by means of documents. The ‘power’ with which the book is concerned is ‘power to’ more than ‘power over’.2 ‘Protocol’ in the title is understood in a sense transferred from the world of computing as ‘A (usually standardised) set of rules governing the exchange of data’ (Oxford English Dictionary). The implicit analogy with software is not inappropriate, since an argument running through the book will be that cleverly designed systems compensated for the inadequacies of the ‘hardware’ of papal government – for its lack of a properly financed bureaucratic infrastructure.

The breakaway cardinals returned to Avignon, taking much of the administration with them. The Roman papacy adapted by imitating the type of letter called a ‘brief’ used by some secular systems. Briefs were written by a different set of men, and before long distinguished by humanistic script. From this time on a dual system operated: Chancery and Secretariate. Initially the latter was for high-level letters but in the later fifteenth century it took on routine business too. Another post-Schism innovation was the sale of offices. Apparently absurd, this bound the upper classes of Italy to the papacy. After the Council of Trent papal government was drastically reorganised. The book enters scantily researched territory in attempting to map the changes in the functioning of the Penitentiary, the processes behind the production of letters by the Chancery and of briefs by the secretaries, and at the Congregations of the Council and of the Inquisition. The documentation generated by these two-sub-systems on the problem of whether Calvinist baptism was valid (for example) is of a kind that medievalists can only envy.