In the summer of 1535, Ferrante Gonzaga came to the aid of the imperial army who had just launched a successful eight-hour attack on the port of Halq al-Wadi (Goletta). Ferrante and his small garrison of Italian soldiers made the journey across the Sea of Sicily to northern Africa, arriving at Halq al-Wadi as Charles V finalised his plans for an attack on Tunis. Literally translated as “river's throat,” Halq al-Wadi sat on a narrow spit of land some 15 kilometres east of the capital, separated by the shallow lagoon of the city's lake. The imperial army would need to navigate along the lake's shores to reach the citadel of which the Greek-Ottoman corsair, Barbarossa, had seized control almost a year earlier. The arrival of Italian reinforcements energised Charles's squadrons and they launched a successful assault on the citadel. Within days, the imperial army had claimed the city of Tunis and its port.

The Italian captain almost immediately wrote to his brother, Cardinal Ercole Gonzaga, to deliver the felicitous news. The letter, dated July 28, 1535, was published in quarto (approximately 24 cm x 30.5 cm) in Rome by Antonio Blado (1490–1567), the official papal printer. Its circulation is unclear, but there are numerous surviving copies across Italian and European libraries, particularly in German-speaking territories where a German translation, “Warhafftige Newe Zeytung des Kayserlichen Sigs zu Thunis geschehen.