General Auguste-Jean-Gabriel de Caulaincourt (1777-1812) was the brother of Napoleon's chief diplomatic aide (Armand-Augustin Louis, Marquis de Caulaincourt), and is most famous for his death in battle at Borodino.
Auguste entered the army in 1792, joining the cavalry. He was wounded at the battle of Marengo (1800). In 1804 he became aide-de-camp to Louis Bonaparte. He fought at Austerlitz (1805). In 1806 Louis was made King of Holland, and Auguste became his master of horse.
In 1808 he was promoted to general of brigade and returned to France. He served in Spain, where he was promoted general de division in 1809. Poor health forced his return to France, but in 1810 he was made a count.
During the 1812 campaign he was in charge of Napoleon's Imperial Headquarters. At Borodino he was sent to replace the popular cavalry general Louis-Pierre Montbrun, who had just been killed. When he reached his new headquarters Auguste found Montbrun's aides in tears. He rallied them, telling the 'Follow me. Weep not for him, but come and avenge his death!'
Murat ordered Auguste to lead his new II Cavalry Corps in an attack on the Great Redoubt, one of the key positions in the Russian lines. August was aware that this would be a difficult task, and replied 'You shall see me there presently, dead or alive'. He was indeed killed just outside the redoubt, although it was probably not his cavalry corps that actually captured the Russian position.