One of the great 'What Ifs' of military history, the Battle of Marengo 1800 firmly secured Napoleon's position as First Consul. Having returned from Egypt and seized power, Napoleon led the Army of the Reserve over the Alps against the Austrian Army besieging Genoa. On the morning of 14th June, Melas, the Austrian commander, launched a surprise attack. The attack initially drove the French back to Marengo village and despite committing the Consular Guard, by 3pm the French were retreating. Believing he had won, the wounded Melas made the decision to leave the field to General Zach. This book describes the run up to that fateful battle and details how the arrival of Desaix's Division led by Kellerman's cavalry threw the Austrians into confusion and turned the battle in Napoleon's favour.