The fruitlessness of research in the archives of the Bastille, and the importance of the political events which were happening, diverted the attention of the public for some years from this subject. In the year 1800, however, the 'Magazin encyclopedique' published (vol. vi. p. 472) an article entitled 'Memoires sur les Problemes historiques, et la methode de les resoudre appliquee a celui qui concerne l'Homme au Masque de Fer', signed C. D. O., in which the author maintained that the prisoner was the first minister of the Duke of Mantua, and says his name was Girolamo Magni.
In the same year an octavo volume of 142 pages was produced by M. Roux-Fazillac. It bore the title 'Recherches historiques et critiques sur l'Homme au Masque de Fer, d'ou resultent des Notions certaines sur ce prisonnier'. These researches brought to light a secret correspondence relative to certain negotiations and intrigues, and to the abduction of a secretary of the Duke of Mantua whose name was Matthioli, and not Girolamo Magni.
In 1802 an octavo pamphlet containing 11 pages, of which the author was perhaps Baron Lerviere, but which was signed Reth, was published. It took the form of a letter to General Jourdan, and was dated from Turin, and gave many details about Matthioli and his family. It was entitled 'Veritable Clef de l'Histoire de l'Homme au Masque de Fer'. It proved that the secretary of the Duke of Mantua was carried off, masked, and imprisoned, by order of Louis XIV in 1679, but it did not succeed in establishing as an undoubted fact that the secretary and the Man in the Iron Mask were one and the same person.
It may be remembered that M. Crawfurd writing in 1798 had said in his 'Histoire de la Bastille' (8vo, 474 pages), "I cannot doubt that the Man in the Iron Mask was the son of Anne of Austria, but am unable to decide whether he was a twin-brother of Louis XIV or was born while the king and queen lived apart, or during her widowhood." M. Crawfurd, in his 'Melanges d'Histoire et de Litterature tires dun Portefeuille' (quarto 1809, octavo 1817), demolished the theory advanced by Roux-Fazillac.
In 1825, M. Delort discovered in the archives several letters relating to Matthioli, and published his Histoire de l'Homme au Masque de Fer (8vo). This work was translated into English by George Agar-Ellis, and retranslated into French in 1830, under the title 'Histoire authentique du Prisonnier d'Etat, connu sons le Nom de Masque de Fer'. It is in this work that the suggestion is made that the captive was the second son of Oliver Cromwell.
In 1826, M. de Taules wrote that, in his opinion, the masked prisoner was none other than the Armenian Patriarch. But six years later the great success of my drama at the Odeon converted nearly everyone to the version of which Soulavie was the chief exponent. The bibliophile Jacob is mistaken in asserting that I followed a tradition preserved in the family of the Duc de Choiseul; M. le Duc de Bassano sent me a copy made under his personal supervision of a document drawn up for Napoleon, containing the results of some researches made by his orders on the subject of the Man in the Iron Mask. The original MS., as well as that of the Memoires du Duc de Richelieu, were, the duke told me, kept at the Foreign Office. In 1834 the journal of the Institut historique published a letter from M. Auguste Billiard, who stated that he had also made a copy of this document for the late Comte de Montalivet, Home Secretary under the Empire.
M Dufey (de l'Yonne) gave his 'Histoire de la Bastille' to the world in the same year, and was inclined to believe that the prisoner was a son of Buckingham.
Besides the many important personages on whom the famous mask had been placed, there was one whom everyone had forgotten, although his name had been put forward by the minister Chamillart: this was the celebrated Superintendent of Finance, Nicolas Fouquet. In 1837, Jacob, armed with documents and extracts, once more occupied himself with this Chinese puzzle on which so much ingenuity had been lavished, but of which no one had as yet got all the pieces into their places. Let us see if he succeeded better than his forerunners.
The first feeling he awakes is one of surprise. It seems odd that he should again bring up the case of Fouquet, who was condemned to imprisonment for life in 1664, confined in Pignerol under the care of Saint-Mars, and whose death was announced (falsely according to Jacob) on March 23rd, 1680. The first thing to look for in trying to get at the true history of the Mask is a sufficient reason of state to account for the persistent concealment of the prisoner's features till his death; and next, an explanation of the respect shown him by Louvois, whose attitude towards him would have been extraordinary in any age, but was doubly so during the reign of Louis XIV, whose courtiers would have been the last persons in the world to render homage to the misfortunes of a man in disgrace with their master. Whatever the real motive of the king's anger against Fouquet may have been, whether Louis thought he arrogated to himself too much power, or aspired to rival his master in the hearts of some of the king's mistresses, or even presumed to raise his eyes higher still, was not the utter ruin, the lifelong captivity, of his enemy enough to satiate the vengeance of the king? What could he desire more? Why should his anger, which seemed slaked in 1664, burst forth into hotter flames seventeen years later, and lead him to inflict a new punishment? According to the bibliophile, the king being wearied by the continual petitions for pardon addressed to him by the superintendent's family, ordered them to be told that he was dead, to rid himself of their supplications. Colbert's hatred, says he, was the immediate cause of Fouquet's fall; but even if this hatred hastened the catastrophe, are we to suppose that it pursued the delinquent beyond the sentence, through the long years of captivity, and, renewing its energy, infected the minds of the king and his councillors? If that were so, how shall we explain the respect shown by Louvois? Colbert would not have stood uncovered before Fouquet in prison. Why should Colbert's colleague have done so?
It must, however, be confessed that of all existing theories, this one, thanks to the unlimited learning and research of the bibliophile, has the greatest number of documents with the various interpretations thereof, the greatest profusion of dates, on its side.