The forgery was created by Charles Bertram, an eighteenth century Englishman then living in Copenhagen. He first disclosed the existence of De Situ Britanniae in 1747 and made his copy of it available in London in 1749, where it was kept in the Arundel Library of the Royal Society. The work was published by Bertram in 1757. De Situ Britanniae was not debunked as a forgery until the middle of the nineteenth century, by which time its misinformation had been incorporated into virtually every publication of ancient British history.
Once it had been accepted as genuine, De Situ Britanniae exerted a profound effect upon subsequent theories, suppositions, and publications of history. It was the premier source of information (and sometimes the only source) for well over 100 years.
It contained 18 "iters" (of the type found in the legitimate Antonine Itinerary), compiled from fragmentary accounts of a Roman general, adding over 60 new and previously unknown stations to those mentioned in the legitimate account. Best of all, it filled up the entire map of Scotland with descriptions and the names of peoples, the part of Britain about which the least was known with any certainty.
It would later be determined that it was actually a clever mosaic of information gleaned from the works of Caesar, Tacitus, William Camden, John Horsley, and others, enhanced with Bertram's own fictions.
The end did not come until 1845. In that year the German writer Karl Wex effectively challenged the authority of De Situ Britanniae in the Rheinisches Museum. He simply noted that De Situ Britanniae contained impossible and improbable technical errors, such as its inclusion of transcription errors that had been introduced in the fifteenth century, and so could not be the work of a fourteenth century monk. His work was translated into English and printed by the Gentleman's Magazine in October of 1846.
The final confirmation that De Situ Britanniae was spurious came in 1869, a quarter century after Wex's publication. The Speculum written by the real Richard of Cirencester was examined between 1863 and 1869 by J. E. B. Mayor, the librarian of the University of Cambridge, and Mayor included a 90-page detailed condemnation of De Situ Britanniæ.
For example, the 1911 Encyclopedia Britannica account which asserts that Thomas Reynolds (in his 1799 Iter Britanniarum) was "skeptical as to the value of Bertram's manuscript" is false or badly worded. Reynolds was skeptical of the quality of Richard of Cirencester's information, but did not express doubts about the validity of the manuscript.
Accounts of the debunking mentioning an 1838 comment by the English Historical Society fail to describe that 1838 comment. In that year, the English Historical Society felt compelled to justify the omission of De Situ Britanniae from the republication of ancient materials of English history. However, the justification states that this was on the grounds that a search for the original manuscript was pending, and was not for any stated reason relating to the validity of Bertram's copy.
Accounts attributing the debunking to an 1867 effort by B. B. Woodward may have been honestly presented, but that 1867 effort itself is not unassailable. In 1866 and 1867, Bernard Bolingbroke Woodward, the librarian of Windsor Castle, wrote a series of articles in the Gentleman's Magazine that challenged the validity of De Situ Britanniae. However, his characterisation of De Situ Britanniae as " plainly a clumsy forgery by an unpractised hand, not a tracing or copy from a genuine original " is curious, to say the least. This same document had been examined back in 1749 by Caseley, the keeper of the Cotton Library, and as late as 1840 Sir. F. Madden of the manuscript department of the British Museum had not only expressed his belief in its validity, but had also criticised the English Historical Society for its 1838 omission of De Situ Britanniae in its list of important works.
The works of those who accepted and used the Bertram's fictions were disparaged, accompanied by charges of "antiquarianism" and sloppy scholarship. Edward Gibbon is among the most notable to be so criticised, but he was never more than one person out of the entirety of the academic world that had accepted the forgery without criticism.
The first use of the name Pennines to describe the English mountain range is from De Situ Britanniae. Quoting:
This province is divided into two equal parts by a chain of mountains called the Pennine Alps, which rising on the confines of the Iceni and Carnabii, near the river Trivona [Trent ], extend towards the north in a continued series of fifty miles.In 1853, Arthur Hussey listed several names in De Situ Britanniae that he could not trace to another source, and the Pennine Alps was one of them.
In his 2004 book Names and History: People, Places and Things, George Redmonds provided a modern assessment. He comments at length on the strange omission of the etymology of the Pennines in the serious literature regarding that area of England, including publications on place-name origins of Derbyshire and Lancashire by respected authors. He finally learns that the origin of the name is from De Situ Britanniae and that "nor do we know any name for the whole range before the eighteenth century." There follows a discussion of the forgery and the fact that a number of its inventions had found their way into the Ordnance Survey maps; and that the true origin of the name was known by serious authors, most of whom simply chose not to speak of it. He also notes that the mountains had been called by various names in the past, and that there were allusional references to the mountains as "our Appenines" as early as the 1630's (and perhaps before that), so likely Bertram simply invented a name that was easy for people to accept as fact.