After his victory at Montenotte, Bonaparte swung the main weight of his offensive to the west against FML Michelangelo Colli's 21,000-strong Sardinian army. To keep Beaulieu's Habsburg army from interfering, the French commander sent André Masséna's division to seize Dego to the north. On 13 April, General of DivisionPierre Augereau attacked FML Giovanni di Provera's weak Austrian Auxiliary Corps east of Millesimo and defeated him. To cover the withdrawal of his command, Provera retreated to Cosseria Castle with part of the Hasbsburg GyulaiFreikorps and two grenadier companies of the Strassoldo Infantry Regiment # 27. Colonel Filippo Del Carretto's newly arrived Sardinian 3rd Grenadier battalion soon joined Provera. Bonaparte ordered the partly ruined hilltop castle to be taken. Augereau and General of Division Meynier's divisions mounted repeated assaults, but the allied garrison resisted stoutly. After leading the last attack of the day, Colonel Barthélemy Joubert wrote,
Nothing more terrible could be imagined than the assault, where I was wounded passing through a loophole; my carabiniers held me up in the air, with one hand I grasped the top of the wall. I parried the stones with my saber, and my whole body was the target for two entrenchments dominating the position ten paces off.
That evening, Augereau invested the castle while Bonaparte regrouped his forces. Early the next morning Augereau summoned the castle to surrender, whereupon Provera capitulated. By that time his men were out of food, ammunition, and water. The report that Bonaparte wrote to the French government regarding the actions that took place around Millesimo, and which he called "The Battle of Millesimo" is confusing, and perhaps even deliberately misleading, as it is probable that Bonaparte did not want to reveal at the time how serious French casualties had been, and how close he had been to having his plans seriously compromised. There was, in fact, no real battle at Millesimo itself, but rather a confused action on 13 April, in which a number of small enemy units were driven back, followed by a short but very costly siege of the castle of Cosseria, which was defended by only about a thousand Austrians and Piedmontese under Provera and Del Carretto. It was only after the defenders had been forced to surrender the castle on 14 April, due to lack of ammunition, food and water, that the French advance inland could continue in safety. Bonaparte later admitted to the Piedmontese chief-of-staff, Colonel Joseph Costa that the siege of Cosseria had been a mistake and had been due to his impatience. It was probably because he wanted to cover up this mistake that Bonaparte's report of the "Battle of Millesimo" was so misleading.
Results
The French lost 700 men in their fruitless attacks on 13 April. Provera's 988 men suffered only 96 killed and wounded, but the remainder became prisoners of war. The French Adjutant General Jean Quenin and Colonel Pierre Banel, and the Sardinian Del Carretto were killed. Louis Suchet received promotion when his colonel was killed in the attack. Losses in the brief action earlier in the day are not known. The surrender of the castle allowed the French offensive to continue. On 14 April, Masséna won the Second Battle of Dego. Soon after, Bonaparte launched his army in a relentless westward drive against Colli's Austro-Sardinian forces.
Footnotes
Printed materials
Birago, C., Gen. 'La difesa di Cosseria.' Antologia italiana, Giornale di scienze lettere ed arti, 2 : 632-46
Boycott-Brown, Martin. The Road to Rivoli. London: Cassell & Co., 2001.
Costa de Beauregard, C. A. Un homme d'autrefois: souvenirs recueillis par son arrière-petit-fils. Paris, 1879
Napoleon. Correspondence de Napoléon Ier publiée par ordre de l'empereur Napoléon III. Paris, 1858–69
Schels, J. B. 'Die Gefechte in den Apenninen, bei Voltri, Montenotte, Millessimo, Cossaria und Dego, im April 1796.' Oesterreichische Militärische Zeitschrift, Bd. 2 : 123-217