In 1672, Carlo Emanuele II, Duke of Savoy, sought to expand his domains by occupying the town of Savona.
For this purpose, he enlisted Raffaele Della Torre, a condottiere (a mercenary military leader), who hired men, many unsalacious, to betray the town from within.
Marana apparently knew of the plot, but failed to inform the authorities, causing his imprisonment for four years.
Marana is the author of Letters Writ by a Turkish Spy, an epistolary novel that judges the history and manners of Europe, especially of France, of his time from an Oriental perspective.
The French writer and philosopher Montesquieu also drew on this book in his Persian Letters, an epistolary novel published in 1721 criticising the existing absolute monarchy in France in his own time.