Louis-Alexandre Berthier (20 November 1753 – 1 June 1815), 1st Prince of Wagram, Sovereign Prince of Neuchâtel, was a French Marshal and Vice-Constable of the Empire, and Chief of Staff under Napoleon.
He accompanied Napoleon throughout the brilliant campaign of 1796, and was left in charge of the army after the Treaty of Campo Formio. He was in this post in 1798 when he entered Italy, invaded the Vatican, organized the Roman republic, and took the pope Pius VI as prisoner back to Valence (France) where, after a torturous journey under Berthier’s supervision, the pope died, dealing a major blow to the Vatican’s political power which, however, did not prove as ephemeral as that of the First Empire.
If Berthier had been there, I would not have met this misfortune.
No one could have better suited General Bonaparte, who wanted a man capable of relieving him of all detailed work, to understand him instantly and to foresee what he would need.