On the Mediterranean, meanwhile, other engagements were underway.
 In April 1543, the Sultan had placed Hayreddin Barbarossa's fleet at the disposal of the French king.
Barbarossa left the Dardanelles with more than a hundred galleys, raided his way up the Italian coast, and in July arrived in Marseilles, where he was welcomed by François de Bourbon, Count of Enghien, the commander of the French fleet.
 On 6 August, the joint Franco-Ottoman fleet anchored off the Imperial city of Nice and landed troops at Villefranche; a siege of the city followed.
 Nice fell on 22 August, although the citadel held out until the siege was lifted on 8 September.

Barbarossa was by this point becoming a liability; on 6 September, he had threatened to depart if he were not given the means with which to resupply his fleet.
 In response, Francis ordered that the population of Toulon—except for "heads of households"—be expelled, and that the city then be given to Barbarossa, who used it as a base for his army of 30,000 for the next eight months.
Yet Francis, increasingly embarrassed by the Ottoman presence, was unwilling to help Barbarossa recapture Tunis; so the Ottoman fleet—accompanied by five French galleys under Antoine Escalin des Aimars—sailed for Istanbul in May 1544, pillaging the Neapolitan coast along the way.

In Piedmont, meanwhile, a stalemate had developed between the French, under the Sieur de Boutières, and the Imperial army, under Alfonso d'Avalos; d'Avalos had captured the fortress of Carignano, and the French had besieged it, hoping to force the Imperial army into a decisive battle.
 During the winter of 1543–44, Francis significantly reinforced his army, placing Enghien in command.
 D'Avalos, also heavily reinforced, advanced to relieve Carignano; and, on 11 April 1544, Enghien and d'Avalos fought one of the few pitched battles of the period at Ceresole.
 Although the French were victorious, the impending invasion of France itself by Charles and Henry forced Francis to recall much of his army from Piedmont, leaving Enghien without the troops he needed to take Milan.
 D'Avalos's victory over an Italian mercenary army in French service at the Battle of Serravalle in early June 1544 brought significant campaigning in Italy to an end.
On the Mediterranean, meanwhile, other engagements were underway.  In April 1543, the Sultan had placed Hayreddin Barbarossa's fleet at the disposal of the French king. Barbarossa left the Dardanelles with more than a hundred galleys, raided his way up the Italian coast, and in July arrived in Marseilles, where he was welcomed by François de Bourbon, Count of Enghien, the commander of the French fleet.  On 6 August, the joint Franco-Ottoman fleet anchored off the Imperial city of Nice and landed troops at Villefranche; a siege of the city followed.  Nice fell on 22 August, although the citadel held out until the siege was lifted on 8 September.
Barbarossa was by this point becoming a liability; on 6 September, he had threatened to depart if he were not given the means with which to resupply his fleet.  In response, Francis ordered that the population of Toulon—except for "heads of households"—be expelled, and that the city then be given to Barbarossa, who used it as a base for his army of 30,000 for the next eight months. Yet Francis, increasingly embarrassed by the Ottoman presence, was unwilling to help Barbarossa recapture Tunis; so the Ottoman fleet—accompanied by five French galleys under Antoine Escalin des Aimars—sailed for Istanbul in May 1544, pillaging the Neapolitan coast along the way.
In Piedmont, meanwhile, a stalemate had developed between the French, under the Sieur de Boutières, and the Imperial army, under Alfonso d'Avalos; d'Avalos had captured the fortress of Carignano, and the French had besieged it, hoping to force the Imperial army into a decisive battle.  During the winter of 1543–44, Francis significantly reinforced his army, placing Enghien in command.  D'Avalos, also heavily reinforced, advanced to relieve Carignano; and, on 11 April 1544, Enghien and d'Avalos fought one of the few pitched battles of the period at Ceresole.  Although the French were victorious, the impending invasion of France itself by Charles and Henry forced Francis to recall much of his army from Piedmont, leaving Enghien without the troops he needed to take Milan.  D'Avalos's victory over an Italian mercenary army in French service at the Battle of Serravalle in early June 1544 brought significant campaigning in Italy to an end.
Italian War of 1542–1546