Cambronne was born in Saint-Sébastien-sur-Loire, a commune near Nantes, in the modern department of Loire-Atlantique. He joined the Grenadiers as a volunteer in 1792, serving under Charles François Dumouriez in Belgium, in the Vendée, took part in the battle of Quiberon, then in the expedition to Ireland under Hoche in 1796. He then joined the Army of the Alps under André Masséna, where he was promoted to command of a grenadier company at the Battle of Zurich (1799).