The exact truth of the story will be best established by a brief history of the antecedent facts. When Louis XIV was at the zenith of his power, supreme at home and an accepted arbiter abroad, he was bent upon consolidating his power in Northern Italy, and eagerly opened negotiations with the Duke of Mantua to acquire the fortress town of Casale. The town was a decisive point which secured his predominance in Montferrat, which gave an easy access at any time into Lombardy. The terms agreed upon were, first, a payment of 100,000 crowns by Louis to the Duke of Mantua and, second, a promise that the latter should command any French army sent into Italy; in exchange, the surrender of Casale. The transaction had been started by the French ambassador in Venice and the principal agent was a certain Count Mattioli, who had been a minister to the Duke of Mantua and was high in his favor. Mattioli visited Paris and was well received by the King, who sent him back to Italy to complete the contract. Now, however, unexplained delays arose and it came out that the great Powers, who were strongly opposed to the dominating influence of France in Northern Italy, had been informed of what was pending. The private treaty with France became public property and there could be no doubt but that Mattioli had been bought over. He had in fact sold out the French king and the whole affair fell through.
Louis XIV, finding himself deceived and betrayed, was furiously angry and resolved to avenge himself upon the traitor. It was pain and anguish to him to find that he had been cheated before all Europe, and in his discomfiture and bitter humiliation he prepared to avenge himself amply. On the suggestion of the French minister at Turin he planned that Mattioli should be kidnapped and carried into France and there subjected to the King's good pleasure. Mattioli was a needy man and was easily beguiled by the Frenchman's promises of a substantial sum in French gold, from the French general, Catinat, who was on the frontier with ample funds for use when Casale should have been occupied. Mattioli, unsuspecting, met Catinat not far from Pignerol, where after revealing the place where his papers were concealed he fell into the hands of the French. Louis had approved of the arrest and insisted only on secrecy, and that Mattioli should be carried off without the least suspicion in Casale. "Look to it," he wrote, "that no one knows what becomes of this man." And at the same time the governor of Pignerol, Saint Mars, was instructed by Louvois, the minister, to receive him in great secrecy and was told, "You will guard him in such a manner that, not only may he have no communication with anyone, but that he may have cause to repent his conduct, and that no one may know you have a new prisoner." The secrecy was necessary because Mattioli was the diplomatic agent of another country and his arrest was a barefaced violation of the law of nations.