Antoine de Guiscard, Abbe de la Bourlie, Marquis de Guiscard
Three manuscript Letter Books (1704-1708) kept by a Franco-British double agent in London which record his efforts to lead a British invasion and… Read more
Published in 1705 by Unpublished.

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LETTER BOOKS OF A FRENCH DOUBLE-AGENT & ASSASSIN AT THE COURT OF QUEEN ANNE by Antoine de Guiscard, Abbe de la Bourlie, Marquis de Guiscard

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Three manuscript Letter Books (1704-1708) kept by a Franco-British double agent in London which record his efforts to lead a British invasion and his charismatic hold over British and European monarchs and ministers - worthy of a full Hollywood treatment. Antoine de Guiscard’s meteoric rise was followed by an equally precipitous fall from grace which ended in a suicidal mission to assassinate Britain’s first minister Robert Harley and the would-be assassin’s body being pickled in a barrel at Newgate Prison for the delectation of visitors. ($15,000)


Born into a French noble family in 1658 Antoine de Guiscard, Abbe de la Bourlie, Marquis de Guiscard became a ‘rake of quality’ who turned military intriguer after being caught up in the brutalities of the Civil War in the Cevennes. Forced into exile in Lausanne he met Richard Hill, the English envoy to Turin, who recommended Guiscard to the British government with whom Guiscard plotted and very nearly carried out the invasion of France during ‘the first World War of modern times’, the War of the Spanish Succession. The charismatic Frenchman was given his own Regiment and put onboard a British Fleet sailing out of Portsmouth in August 1706 - before the weather intervened. As swiftly as he rose Guiscard fell from favour and the historian of espionage Christopher Andrew describes how he ‘sought to transform himself into a double agent working for Louis XIV, was arrested after his treasonable correspondence was intercepted’ and while under interrogation by members of the Cabinet attempted to murder the head of government. Robert Harley survived the knife attack due to a single, heavy gold-thread embroidery button on his coat, but Guiscard perished from his wounds in Newgate Prison where ‘the jailer pickled Guiscard’s corpse in a barrel; put it on display and charged a penny for admission…. No double agent in British history has met a stranger end’ (Christopher Andrew). Guiscard’s treacherous attack alarmed Queen Anne, prompted a security scare and was written up by Jonathan Swift.


The collection comprises three folio-size (32x20cm) manuscript volumes (I, II and III); all uniformly bound in full vellum with a blind double fillet to the boards and external spine straps at the outer hinges, speckled black edges; some loss to the backstrip of Vol III, otherwise bindings in very good condition. Paper with vertical chain lines; unidentified armorial watermark. The manuscripts are laid out on pencil-lined pages and written in 2, possibly 3, secretarial hands. All three volumes have ‘Chapman’ written on the first pastedown in an 18th century hand, probably the name of Guiscard’s principal Secretary who would have had overall responsibility for the letter books in England. Guiscard’s much messier hand appears regularly throughout the manuscripts, correcting and amplifying the copied text. Twice Guiscard used the book to draft heavily corrected letters himself, absent-mindedly signing one of these in full. Though written in Guiscard’s native French (his English was poor to non-existent) these manuscripts are dominated by Guiscard’s dealings with the English crown and government and his plan to invade France from English soil. It seems certain that Volumes II and III were compiled in London; Volume I which covers the events that led to his move to England was probably also compiled retrospectively in this country.

PROVENANCE: Vol II has the bookplate of ‘The Library of The Duchy of Cornwall. Albert Edward Prince of Wales’ (Lee 43) - the future Edward VII. Given the circumstances of Guiscard’s death his London house would have been searched by government agents after his treasonous attack on Robert Harley when these volumes were probably confiscated, later passing through the Royal collections.


The manuscripts - amounting to some 220,000 words - offer a mixture of Memoir, Relacion, Projet, Negociacion, Manifeste, Certificats, Ordonnance and Lettres to and, sometimes with copies, from his correspondents. There are 174 unique documents that vary from 1 to 8 pages in length (c. 500 pages) but this number increases to around 300 items when taking into account documents that appear more than once in different volumes. Among these documents are 6 unique letters and memoranda to Queen Anne; 43 to John Churchill, Duke of Marlborough and 41 to Marlborough’s friend and fellow ‘Duumvir’, Sidney Godolphin. Other correspondents include Henry St John, Viscount Bolingbroke (11) Prince Eugene of Savoy (17) the Prince of Liechtenstein, the Prince of Denmark, Charles III, the Grand Pensionary of Holland and Admiral Sir Cloudesley Shovell.

Volume I covers May 1704 (Guiscard’s exile from France) to late 1706 (shortly after the thwarted invasion): [pp]260 and written from the other end of the MS, pp1-59 (c. 80,000 words). The manuscript begins with what Guiscard has annotated as ‘relation de ce qui m’est arrive d’abord apres ma sortie de france’ - ‘An account of what happened to me before my departure from France’. The layout of this letter-book is fairly informal by comparison with the later two MSS although the 1706 section written at the end of this volume is more systematic as befitted Guiscard’s new status, about to take control of his Regiment and onboard HMS Namur at Torbay in August 1706.

Vol II November 1705- 3 October 1707, [pp]2 Index; [pp] 14 blanks; pp253; preceded by a 2 page Index in a miniscule hand. 7 blank leaves are followed by the main text (c. 60,000 words) which starts 25th November 1705 with a copy letter by Charles III (the Spanish pretender) recommending Guiscard to Queen Anne: ‘negociation d’Engleterre Copie d’une lettre ecrite par Sa Majeste Catholique Charles Troisieme a sa Majeste Britannique en faveur du Marquis de Guiscard, de Barcelone le 25 No.bre 1705’.

A more deliberately constructed letter book which begins noisily with a document that announces Guiscard’s arrival in England where Guiscard secured a substantial pension and a £600 payout from the Queen herself. This placed Guiscard’s domestic affairs on a more secure footing, probably explaining the competent and systematic quality of the manuscript. This volume covers the period of Guiscard’s moment of maximum influence in European affairs when he was taken up by the British government, given high military rank and allowed to mastermind an invasion of France which got as far as embarkation into the English Channel before being foiled by calm weather in August.

Vol III, November 1705-August 1708; 3 page index preceding letter-book text; 333 pages (c. 80,000 words) of manuscript ending in August 1708 followed by 12 blank leaves. A stationer’s note in a contemporary hand appears on the tail of the front pastedown ‘4:M. Superf. Fool cap. E.’ This text overlaps substantially with Vol II until April 1707 when there is a gap until October 1707 (filled by Vol II) after which Vol III continues as the sole authority for these texts. A high quality letter book with corrections in Guiscard’s hand. The presence of 4 terminal blanks suggests that the 3 volumes we have here represent a complete collection.

Writing about Antoine de Guiscard in an article for the British Library Journal in 1982 Peter Jones drew on research into his surviving letters in the Marlborough Papers, BL, and in the Rijksarchief at The Hague; these manuscript letter books with their 220,000 words offer a resource of a different order of magnitude.


From the outset Guiscard displayed unquenchable self-certitude, protesting his right to lead the French emigres in England against Louis XIV: ‘J’ai la confidence entiere de tous les protestans de France Tous les Catholiques ont connoissance de mes desseins.’ His invasion plan was indeed audacious: ‘Le Marquis de Guiscard propose de faire dans la campagne prochaine la conquête de la Savoie et d’abord apres d’entrer en Dauphine…’ Guiscard’s earliest surviving letter to the Duke of Marlborough dates from ‘le 3 Aoust 1705’ by which time his interest had moved from the Mediterranean to the Normandy coasts: ‘Projet d’une Feinte, sur une descent dans la Normandie, et dans la Bretagne’.

From the moment of Guiscard’s arrival in England he set himself as an honest broker with connections across the continent. In a letter to Queen Anne (12.2.1706) he recounts ‘mes negotiations en Engleterres, et en hollande, et des toutes mes allees et venues en piedmont et en dernier lieu en Catalogne.’ He advocated to the Queen her need to grasp England’s chance for Glory: ‘un se grand projet ne seroit ce pas une presomption et une temerite extreme an un etranger de vouloir enlever a la Nation Angloise la gloire de terminer une guerre…’ (p11) (‘A great project - would it not be a presumption and an extreme temerity for a foreigner to want to deprive the English Nation of the glory of ending a war…’) Guiscard’s relationship with the Queen is one of the most interesting aspects of the manuscripts and early in 1706 he went so far as to appeal to the Queen against the laws discriminating against Catholics in England: ‘Permetes moi donc Madame, d’examiner un moment contre quels Catoliques ces loix ont ete faites… II (pp54-60). On the other side Guiscard also took care to protest noisily at Louis XIV’s domestic inequities in a long and passionate open letter: ‘J’ay trois griefs mortels contre le Roy…’

As the British government bent to his will early in 1706 Guiscard prepared to take command of the invasion of France. He devised a personal loyalty oath, and one of very few copied documents in English in the collection is a letter from Secretary of War Henry St John Bolingbroke: ‘My Lord, it being agreed that the Marq.s de Guiscard should be acknowledged in this expedition in the qualitie of a Lieuten.t General … please to give it out in order to the Troops under your command to acknowledge him as such…’ (13 July 1706). Although the letters reveal that the organisational strain of invasion planning was taken by Henry St John Bolingbroke, Secretary of War, Guiscard pestered Marlborough with his requirements that included ‘Vaiseaux de guerre’, transportation vessels, artillery including 12 ‘Pieces de campagne de different qualibres’ and 8 long-range ‘pieces de batteries’ - siege weapons followed by mortars, bombs, grenades etc (1st April 1706). With Marlborough the tone of this correspondence is often intense; with Heinsius and the Dutch positively angry as Guiscard tried to keep them involved in the project: ‘le second obstacle est l’incertitude ou vous pouver etre…’ (5 March 1706)

Ultimately it was the most banal of reasons that thwarted the invasion plan - the weather. By late July Guiscard had assembled troops, boats, munitions and guns in Portsmouth, but the wind dropped and a season of calm set in, making it impossible to sail. On the 20th August St John Bolingbroke wrote to Guiscard that ‘la saison est fort avancee’ and by 25 August he was offering comfort to the warlike Frenchman: ‘Je connois le chagrin que vous aves de voir nos desseins changes…’ The events of late 1706-1708 were disastrous for Guiscard. When the invasion fleet finally sailed it was diverted to Portugal and Guiscard’s regiment almost wiped out. He made the mistake of accusing Marlborough of a failure of nerve: ‘Je suis accessible de desespoir, la vie m’est insupportable la crainte que j’ai des choses me rend plus clair voyant a les prevoir, je vois qu’on ne fait pas asses d’essansion a ce qui je dis… il n’y a aucun autre remede a appliquer’.

An apology to Marlborough follows but the letters show Guiscard becoming aware that he was no longer trusted. He reassured Godolphin that he could keep a secret: ‘Je n’ai jamais pretendu rendre ce papier public, Dieu m’en preserve’ (III p198; 7 October 1707). He issued noisy denials of his public critics such as ‘Reponse a la harangue de Milord Haversham prononcee le mecredi 19 No.bre 1707’, but early in 1708 came new accusations against his integrity from Antoine de Laussac, Chaplain to Earl Rivers. Guiscard attempted a dramatic take-down of his accuser who had ‘debauche la femme qui’il est venu en suits espouser ici, apres avoir change de religion. C’est un homme fort a la table, ou il passe les jours et les nuit.’ Aptly the manuscript ends with a ‘Demande de M. Guiscard’ assuring his unnamed correspondent of ‘du zele et de la fidelite avec les quels je me comporterai dans cette affairs’ ‘the zeal and fidelity with which I will conduct myself in this business' and offering to leave if he doesn’t follow through. Neither did Guiscard leave nor follow through and his life continued to its desperate conclusion.

Full details

Added under Manuscript
Publisher Unpublished
Date published 1705
Subject 1 Manuscript
Signed Yes
Product code 7940

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