Charles François Dumouriez Charles - François du Périer Dumouriez ( 25 January 1739 – 14 March 1823 ) was a French general during the French Revolutionary Wars . He shared the victory at Valmy with General François Christophe Kellermann , but later deserted the Revolutionary Army , became a royalist intriguer during the reign of Napoleon and an adviser to the British government . Early life . Dumouriez was born in Cambrai , on the Scheldt River in northern France , to parents of noble rank . Six years earlier , Cambrai was part of the Belgian provinces , and so Dumouriez would always consider himself a Walloon or French - speaking native of Flanders . His father , Antoine - François du Périer , served as a commissary of the royal army , and educated his son most carefully and widely . The boy continued his studies in Paris at the " Lycée Louis - le - Grand " , and in 1757 began his military career as a volunteer in the campaign of Rossbach . He received a commission for good conduct in action , and served in the later German campaigns of the Seven Years ' War with distinction ; but at the peace he was retired as a captain , with a small pension and the cross of St Louis . Dumouriez then visited Italy and Corsica , Spain and Portugal , and his memoranda to the duc de Choiseul on Corsican affairs at the time of the Corsican Republic led to his re - employment on the staff of the French expeditionary corps sent to the island , for which he gained the rank of lieutenant - colonel . In 1767 Choiseul gave Dumouriez a military command as deputy quartermaster general to the Army of Corsica under the Marquis de Chauvelin . After this , he became a member of the Secret du Roi , the secret service under Louis XV , which gave full scope to his diplomatic skills . In 1770 he undertook a mission into Poland to the Confederation of Bar , where , in addition to his political business , he organized a Polish militia for the War of the Bar Confederation . On 23 May , his Polish soldiers were smashed by the Russian forces of General Alexander Suvorov in the Battle of Lanckorona . The fall of Choiseul ( 1770 ) brought about Dumouriez ' s recall . In 1772 , upon returning to Paris , Dumouriez sought a military position from the marquis de Monteynard , Secretary of State for War , who gave him a staff position with the regiment of Lorraine writing diplomatic and military reports . In 1773 , he found himself imprisoned in the Bastille , where he spent six months , occupying himself with literary pursuits . He was then removed to Caen , where he remained in detention until the accession of Louis XVI in 1774 . Dumouriez was then recalled to Paris and assigned to posts in Lille and Boulogne by the comte de Saint - Germain , the new king ’ s minister of war . Upon his release , Dumouriez married his cousin , a certain " Mademoiselle de Broissy " , but he proved a neglectful and unfaithful husband , and in 1789 the couple separated . Madame Dumouriez took refuge in a convent . In the meantime , Dumouriez had turned his attention to the internal state of his own country , and amongst the very numerous memoranda which he sent to the government was one on the defence of Normandy and its ports , which procured for him in 1778 the post of commandant of Cherbourg , which he administered with much success for ten years . He became a " maréchal de camp " in 1788 , but his ambition was not satisfied . Career during the Revolution . At the outbreak of the Revolution , seeing the opportunity for carving out a new career , he went to Paris , where he joined the Jacobin Club in 1789 . The death of Mirabeau , to whose fortunes he had attached himself , proved a great blow . However , opportunity arose again when , in his capacity as a lieutenant - general and the commandant of Nantes , he offered to march to the assistance of the National Constituent Assembly after the royal family ' s unsuccessful flight to Varennes . In 1790 , Dumouriez was appointed French military advisor to the newly established independent Belgian government and remained dedicated to the cause of an independent Belgian Republic . Minister of War , Louis Lebègue Duportail , promoted Dumouriez from president of the War Council to major - general in June 1791 and attached him to the Twelfth Division , which was commanded by General Jacques Alexis de Verteuil . He then attached himself to the Girondist party and , on 15 March 1792 , became the French minister of foreign affairs . Dumouriez then selected Pierre LeBrun as his first officer for Belgian and Liégeois affairs . The relationship between the Girondists and Dumouriez was not based on ideology , but rather based on the practical benefit it gave to both parties . Dumouriez needed people in the Legislative Assembly to support him , and the Girondists needed a general to give them legitimacy in the army . He played a major part in the declaration of war against Austria ( 20 April ) , and he planned the invasion of the Low Countries . His foreign policy was greatly influenced by Jean - Louis Favier . Favier had called for France to break its ties with Austria . On the king ' s dismissal of Roland , Clavière and Servan ( 13 June 1792 ) , he took Servan ’ s post of minister of war , but resigned it two days later on account of Louis XVI ' s refusal to come to terms with the National Constituent Assembly , and went to join the army of Marshal Luckner . After the " émeute " of 10 August 1792 and Lafayette ’ s flight , he gained appointment to the command of the " Army of the Centre " . At the same moment , France ' s enemies assumed the offensive . Dumouriez acted promptly . His subordinate Kellermann repulsed the Prussians at Valmy ( 20 September 1792 ) , and Dumouriez himself severely defeated the Austrians at Jemappes ( 6 November 1792 ) . After these military victories , Dumouriez was ready to invade Belgium to spread revolution . He was a true revolutionary in the sense that he believed that nations which had undergone a revolution , in this instance France , should give aid to oppressed countries . As his plans were largely limited to Belgium , this tunnel vision sometimes prevented him from acting in the most logical fashion as a commander . Returning to Paris , Dumouriez encountered popular ovation , but he gained less sympathy from the revolutionary government . His old - fashioned methodical method of conducting war exposed him to the criticism of ardent Jacobins , and a defeat would have meant the end of his career . To the more radical elements in Paris , it became clear that Dumouriez was not a true patriot when he returned to Paris on 1 January 1793 and worked during the trial of Louis XVI to save him from execution . Dumouriez had also written a letter to the Convention scolding it for not supplying his army to his satisfaction and for the Decree of 15 December , which allowed the French armies to loot in the territory they had won . The Decree insured that any plan concerning Belgium would fail due to a lack of popular support among the Belgians . This letter became known as “ Dumouriez ’ s declaration of war ” . After a major defeat in the Battle of Neerwinden in March 1793 , he made a desperate move to save himself from his radical enemies . Arresting the four deputy - commissioners of the National Convention who had been sent to inquire into his conduct ( Camus , Bancal - des - Issarts , Quinette , and Lamarque ) as well as the Minister of War , Pierre Riel de Beurnonville , he handed them over to the enemy , and then attempted to persuade his troops to march on Paris and overthrow the revolutionary government . The attempt failed , and Dumouriez , along with the duc de Chartres ( afterwards King Louis Philippe ) and his younger brother , the duc de Montpensier , fled into the Austrian camp . This blow left the Girondists vulnerable due to their association with Dumouriez . Later life and death . Following his defection in April 1793 , Dumouriez remained in Brussels for a short time , and then traveled to Cologne , seeking a position at the elector ’ s court . He soon learned he had become an object of suspicion among his countrymen , the royal houses , aristocracies , and clergy of Europe . In response , Dumouriez wrote and published in Hamburg a first volume of memoirs in which he offered his version of the previous year ’ s events . Dumouriez now wandered from country to country , occupied in ceaseless royalist intrigues , until 1804 when he settled in England , where the British government granted him a pension . He became a valuable adviser to the British War Office in its struggle against Napoleon , though the extent of his aid only became public many years later . In 1814 and 1815 , he endeavoured to procure from Louis XVIII the baton of a marshal of France but failed to do so . He died at Turville Park , near Henley - on - Thames , on 14 March 1823 . Dumouriez ' s memoirs appeared at Hamburg in 1794 . An enlarged edition , " La Vie et les mémoires du Général Dumouriez " , appeared at Paris in 1823 . Dumouriez also wrote a large number of political pamphlets . References . Other sources . The 1911 " Encyclopaedia Britannica " , in turn , gives the following references :