Battle of Marengo
War of the Second Coalition · Marengo, near Alessandria, Piedmont, Italy
Summary
On 14 June 1800 (25 Prairial Year VIII), near Alessandria in Piedmont, Bonaparte, then First Consul, reversed a surprise attack by Field Marshal Melas's Austrian army. After a difficult morning in which Victor and Lannes gave ground, Desaix's corps arrived and a late-day counterattack turned impending French defeat into decisive victory.
Historical context
The 1800 Italian campaign formed part of the War of the Second Coalition. Bonaparte crossed the Alps in May and reached Milan on 2 June. The Austrians sought to exploit stretched French lines after Montebello to cut Bonaparte's army in two near Alessandria.
Tactics
Melas launched a surprise offensive on 14 June: Victor's and Lannes's French gave ground on the Fontanone. Bonaparte recalled forces dispersed north and south. In late afternoon, Desaix's reinforcing corps enabled a counterattack that swung the battle and precipitated Austrian retreat.
Consequences
Desaix was killed in action. The victory consolidated Bonaparte's power in Paris after the Brumaire coup. The Austrians negotiated the Convention of Aranjuez then the Treaty of Lunéville (1801), reversing the coalition's string of defeats and restoring French dominance in Italy.