December 14th, 1677.
Sire,
I take the liberty of bearing testimony to your Majesty, that among the great Ministers, whom, in your supreme wisdom, you have sent at different times into Italy, your ambassador at Venice, the Abbé d’Estrades, ought to be distinguished for his skill and his zeal to seize every occasion, which may seem to offer him the improvement or the aggrandizement of your territories.
This Ambassador having confided to me, that, in order to succeed in the enterprize that you meditate against the territories of Milan, it would be necessary to detach the Duke of Mantua from the Austrian party, and to draw him into that of your Majesty, I am anxious to contribute every thing in my feeble power for the success of this object. Your Majesty will be made acquainted with all that has passed by the despatches of the Ambassador. For myself, I bless the destiny, which procures me the honour of serving so great a monarch, whom I regard and revere as a demi-god.
I will transmit to your Majesty all that I shall learn respecting Casale, which has been fortified by one of the most skilful engineers of the Milanese. This engineer has promised us a plan of all the fortresses of that State, and even, if your Majesty commands him, he will separate himself from the service of Spain, who does not know how to recompense properly the services and the talents of those who serve her with fidelity. I am convinced it would be useless in me to enlarge upon the importance of the fortress of Casale. Your Majesty must remember, that at different times it has arrested the progress of many armies, and that it is the only bulwark, upon which depends the loss or the preservation to the Spaniards of the territories of Milan; territories, which for more reasons than one, ought to belong to your Majesty’s crown.
It is known that the Austrians are at this moment arming, in order to obtain possession by surprize of Casale, to the prejudice of the Duke Ferdinand, my master, the lawful possessor of it.
This Prince, nephew of Charles[161] the first, (which latter Prince was rather French than Italian, and by whose intervention the fortress of Pignerol has remained in the possession of your royal house); this Prince, I say, Ferdinand, will make known, in fit time and place, that he has not degenerated from his ancestors; he has promised to serve you with the greatest fidelity, and to fight for you in a manner worthy of his birth; and as he is extremely anxious to acquire glory, I trust your Majesty will have reason to applaud his conduct in your armies. By the confession of even the most skilful political observers, he is free from the suspicions, which may fall upon the other Italian Sovereigns. The Abbé d’Estrades knows that his Highness has communications with other great personages, who complain with reason of the insupportable yoke of the Spaniards, and who will take arms with him to combat, and to drive as quickly as possible from Italy, a power which is only established there to oppress it. If destiny willed it so, I have no doubt that the other Princes of this country would be happy to enjoy a stable peace under the auspices of your Majesty. I offer up vows for the progress of your victorious arms, and I pray God to prolong your days for the consolation of the world, &c.
Hercules A. Matthioli.[162]