Louis Auguste Le Tonnelier de Breteuil Louis Charles Auguste le Tonnelier , baron de Breteuil , baron de Preuilly ( 7 March 1730 – 2 November 1807 ) was a French aristocrat , diplomat , statesman and politician . He was the last Prime Minister of the Bourbon Monarchy , appointed by King Louis XVI only one hundred hours before the storming of the Bastille . Soldier and ambassador . Breteuil was born in 1730 at the chateau of Azay - le - Ferron ( Indre ) into a well - connected aristocratic family : one of his relations was confessor to the king ' s cousin and another was the famed mathematician and linguist Émilie , marquise du Châtelet - Laumont . He received an excellent education in Paris and later joined the army , where he fought in the Seven Years ' War . In 1758 he left the army and joined the French Foreign Ministry . He was quickly appointed French ambassador to the elector of Cologne , where he proved to have valuable diplomatic skills . Two years later he was sent to St Petersburg as the French ambassador to Imperial Russia , where he arranged to be temporarily absent from his post at the time of the palace revolution by which Catherine II was placed on the throne . In 1769 he was sent to Stockholm ( Sweden ) , and subsequently represented his government at Vienna ( Habsburg Monarchy ) , Naples ( Kingdom of Naples ) , and again at Vienna until 1783 . In Sweden , he became a favourite friend of the young King Gustavus III , but Catherine the Great of Russia disliked him . Others saw Breteuil as a loud and impulsive fool , Joseph II and several high - ranking Austrian politicians sneered at the " " fool " " behind closed doors . Household Minister . After he returned to France , Breteuil was appointed Minister of the King ' s Household . In this capacity he introduced considerable reforms in prison administration . He was a liberal and humanitarian minister , and succeeded in moderating the censorship laws . He believed passionately that the monarchy should encourage intellectual s , and not view them as enemies . In 1784 he was named to a position in the Académie des Inscriptions et Belles - Lettres . Breteuil ' s time as Household Minister corresponded with the infamous Affair of the Necklace , which pitted him against his enemy , the Cardinal de Rohan . Breteuil ' s loyalty to Queen Marie Antoinette earned him her gratitude and trust at this difficult time . Unfortunately , Breteuil underestimated the strength of public sympathy for those responsible , and his direct attack on Rohan left the Queen open to public humiliation . He presently came into collision with Charles Alexandre de Calonne , who demanded his dismissal in 1787 . On 24 July 1788 , Breteuil resigned , exhausted by the struggle for power in the King ' s Council . He then asked to be allowed to say farewell to the queen . Marie - Antoinette did not resent him for his handling of the affair , and even promised to help him in future if she could . Appointment as Prime Minister . As France became increasingly unstable , Breteuil retired to his château in Dangu . Though Breteuil was disgusted with French politics at the time , he remained absolutely loyal to the Monarchy , despite his liberal views on social culture . He complained that " " anybody who dares to stand up for the old ways is despised " " and claimed that " " we are rushing like madmen to our destruction " " . Breteuil was contacted by conservative members of the queen ' s circle in 1789 . He agreed to become Prime Minister once they had ousted Jacques Necker from the post . Necker was popular , but royalists saw him as a dangerous publicity - seeker and a radical . A carefully orchestrated plan was drawn - up by Breteuil , the duchesse de Polignac , the King ' s brother the comte d ' Artois and with the support of Marie - Antoinette . However , unable to restrain his hatred for Necker , the comte d ' Artois rushed ahead with the plan too early . Necker was dismissed weeks before Breteuil believed he should be . Breteuil was appointed Prime Minister on 12 July 1789 . Partly as a result of Necker ' s dismissal , the Bastille was stormed on 14 July . Government in exile . In such dangerous times , many prominent Royalists were forced to flee France . The duchesse de Polignac escaped to Switzerland , and Louis XVI sent the comte d ' Artois abroad to save him from assassination . Breteuil went first to a spa town in Imperial territory before journeying to Switzerland with the first party of " émigrés " . The French royal family were placed under house arrest in October . The hatred and violence surrounding them gave the Queen reason to fear for her family ' s life . To Marie Antoinete ' s horror and disgust , Artois ( living in Turin ) then appointed Calonne to his council . Marie Antoinette despised Calonne , and his appointment was the end of her friendship with her brother - in - law . She was convinced that he could no longer be trusted to preserve the monarchy ' s best interests . It was Marie Antoinette ' s decision , therefore , that Breteuil be appointed Prime Minister - in - exile . Louis XVI supported her in this move , but it was Marie Antoinette who took the initiative and formalised Breteuil ' s appointment . In effect , he was now the Royal Family ' s chief diplomat abroad . At Soleure , in November 1790 , he received from Louis XVI exclusive powers to negotiate with the European courts , and in his efforts to check the ill - advised diplomacy of the " émigré " princes , he soon brought himself into opposition with his old rival Calonne , who held a chief place in their councils . Varennes . In coordination with Marie Antoinette ' s favourite , the Swedish count Axel von Fersen , Breteuil organised the royal family ' s escape from Paris in 1791 , garnering support from King Gustavus III of Sweden . The attempt almost succeeded , but was foiled at the last minute by Jean - Baptiste Drouet , the Republican son of a local postmaster . It was also Breteuil who negotiated with the monarchies of Europe to persuade them to fight the French Revolution . After the failure of the flight to Varennes , Breteuil received instructions from Louis XVI , designed to restore amicable relations with the princes . His distrust of the king ' s brothers and his defence of Louis XVI ' s prerogative were to some extent justified , but his intransigeant attitude towards these princes emphasized the dissensions of the royal family in the eyes of foreign sovereigns , who looked on the comte de Provence as the natural representative of his brother and found a pretext for non - interference on Louis ' s behalf in the contradictory statements of the negotiators . His attempts were ultimately in vain . The Bourbon monarchy in France was overthrown in 1792 , followed by massacres of many Royalists in Paris . In January 1793 , Louis XVI was executed . In October , Marie Antoinette met a similar fate . In 1795 , their son , Louis XVII died in prison . Later life . Breteuil himself was the object of violent attacks from the party of the princes , who asserted that he persisted in exercising powers which had been revoked by Louis XVI . After the execution of Marie Antoinette he retired into private life near Hamburg . Breteuil spent the next decade in exile . His loyalty to the House of Bourbon had ended with the death of the little boy - king in 1795 . He was hated by Louis XVI ' s two surviving brothers , particularly by the comte d ' Artois . Breteuil was allowed to return to France in 1802 by Napoleon Bonaparte , having made his peace with the First French Empire . He tried to urge other Royalists to join him , but he was largely unsuccessful . Most preferred to stay loyal to the exiled Bourbons . Breteuil died in France in 1807 . A Bourbon Restoration occurred in 1814 , but was deposed again by the 1830 July Revolution . Legacy . Breteuil ' s secret correspondence with Louis XVI and Marie Antoinette was recently discovered in an Austrian castle by British historian Professor Munro Price . His findings were presented in " The Fall of the French Monarchy : Louis XVI , Marie - Antoinette and the baron de Breteuil " , ( sometimes titled " The Road from Versailles " ) . To date , it is the most comprehensive book on Breteuil ' s career and his fight to save the French Monarchy . The Pavillon de Breteuil , in Sèvres , France , home of the International Bureau of Weights and Measures , is named after the baron .