The 1640 siege of Turin (22 May–20 September 1640) was a major action in two distinct wars: the Franco-Spanish War (1635–59) and the Piedmontese Civil War. When Thomas Francis, Prince of Carignano and his Piedmontese faction captured Turin, the French garrison supporting the Regent Christine Marie of France retired within the citadel and continued to resist. A Franco-Piedmontese army led by Henri de Lorraine, count of Harcourt and Henri de la Tour d'Auvergne, Vicomte de Turenne invested the forces under Prince Thomas within the city. Finally, a Spanish army under Diego Felipez de Guzmán, Marquis of Leganés appeared and encircled the French besiegers. In this triple siege, the Spanish army surrounded the French army which surrounded Prince Thomas' Piedmontese who surrounded the French contr