Siege of Kehl ( 1733 ) The Siege of Kehl ( 14 – 28 October 1733 ) was one of the opening moves of the French Rhineland campaign in the War of the Polish Succession , at the fortress town of Kehl in the upper Rhine River valley . A large French army under the command of the Duke of Berwick besieged and captured the fortress , which was lightly garrisoned and in poor condition . Context . On the death of Augustus II on 1 February 1733 , the Polish throne was claimed by both his son , Augustus III , and by Stanislas I , father in law of Louis XV . Whilst a body double ostensibly left Brest by sea , Stanilas crossed Germany incognito and arrived at Warsaw on 8 September . On 12 September Stanislas was elected king of Poland by the diet . On his election Russia and Austria ( backing Augustus III ) invaded Poland . By 22 September Stanislas , who did not have a proper army , had to take refuge in Danzig ( now known as Gdansk ) , there to await the French help he had been promised . On 5 October , Augustus III was proclaimed king under protection from Russian forces at Warsaw . Great Britain , the Dutch Republic , Sweden , Denmark and the Republic of Venice recognised that Austro - Russian aggression against Poland was the casus belli and pledged to remain neutral . Spain , coveting the Kingdom of Naples and Sardinia , which coveted the Duchy of Milan , sided with France . Louis XV ' s courtiers ( including the princes of Conti and Eu , the counts of Clermont , Charolais and Belle - Isle , the duc de Richelieu , but also Maurice de Saxe , Augustus III ' s half - brother and the former lover of Anna Ivanovna , now the tsarina of Russia ) joined up under marshal James FitzJames to form an army for invading the Rhineland with the objective of distracting Austria from events in Poland and gaining the Duchy of Lorraine . Prelude . The village and fortress of Kehl was located near the Margraviate of Baden ( now part of the German state of Baden - Württemberg , but then part of the Holy Roman Empire ) , just across the Rhine River from the French city of Strasbourg . The fortress at Kehl , and that at Philippsburg to the north , provided strategic military control over major crossings of the upper Rhine , which formed the boundary between French - controlled Alsace and the various principalities of the empire . Nominally the responsibility of the emperor , maintenance and defense of the fortress belonged to the Swabian Circle , which was largely dominated by the Duchy of Württemberg . Although some imperial troops were stationed there in January 1733 , the commander of the fortress was the Württembergian lieutenant general Baron Johann August von Phull , and most of its garrison consisted of Swabian troops . When the war broke out , numerous works to repair and expand the fortress were underway , but key defenses near the Rhine were incomplete . On 12 October , French troops under Belle - Isle and Silly marched into the Duchy of Lorraine and seized its capital , Nancy . Control over the remainder of Lorraine was rapidly established , and the two commanders left garrisons throughout the duchy before sending the bulk of their forces into Alsace to focus on the campaign on the Rhine . Also on 12 October , Berwick ordered troops from the Strasbourg encampment to cross the Rhine . At a point near Auenheim , about below Kehl , they constructed a ship bridge and crossed 4 , 000 men to the east bank . Near Goldscheuer , above the fortress , they began constructing another bridge . Two days later , the bulk of the Berwick ' s army had crossed the Rhine . General Phull , when the French began their movements , destroyed the bridge between Kehl and Strasbourg , and also destroyed those houses and other buildings outside the fortress that might provide the attacking French any sort of shelter . Siege . Berwick first ordered the construction of a line of circumvallation . Local villagers were among those pressed into service for its construction , which was anchored at both ends by the Rhine , above and below the fortress . Berwick ' s quartermasters also made demands to the surrounding villages for the delivery of provisions to the besiegers . The Duke of Württemberg signed a supply agreement that he characterized in reports to the emperor as being concluded under the greatest duress . By 17 October Berwick was ready to begin digging siege lines , and it became apparent to Phull that the fortress ' river - facing hornwork was Berwick ' s target when the latter began construction of batteries on the island between Kehl and Strasbourg . On 18 October Phull issued detailed instructions to his commanders concerning the tactics of defense and retreat . The hornwork was to be held until it was either breached or its artillery rendered useless , at which point the defenders were to fall back first to the covered way between the hornwork and the main fortress , and then to the fortress proper . The French began digging siege trenches on the night of 19 October . By 21 October the siege lines reached an unfinished lunette on the Rhine - facing side of the fortress , and the French began setting up a battery there on 23 October . The defenders were by this time reduced to musket fire and grenades , as most of their artillery had been dismounted or destroyed by enemy fire . On 23 October the French opened fire not only on the hornwork , but also began battering the walls of the main fortress with cannon fire . After two failed assaults by Berwick ' s grenadiers , they succeeded in briefly occupying the hornwork ; it was reoccupied by the Germans the next day . The defenders attempted a sortie against the French positions near the hornwork , but it was repulsed . By 27 October , the French had established numerous batteries and were mercilessly battering the main fortification . About 4 pm on 28 October , the French barrage started a fire on the hornwork that was severe enough that its commander requested permission from Phull to withdraw ; this permission was granted . Phull then held a council , in which it was determined that only 500 men were combat - ready , and that the fortress might hold out at most three more days . Consequently Phull raised the white flag around 8 pm on 28 October . The garrison marched out of the fortress on 31 October with the full honors of war , and was escorted to the imperial defense line at Ettlingen . Aftermath . The onset of bad weather ended the French campaign for the year , and Berwick , after consolidating his control over the area , quartered his troops for the winter on the French side of the Rhine . In 1734 Berwick continued the campaign down the Rhine , successfully flanking the Austrian defense line at Ettlingen , and continuing with the siege of Philippsburg , during which he was killed by a shell . That siege was successfully concluded by his second in command , the marquis d ' Asfeld , and marked the end of significant military operations in the Rhine valley for the war . Pursuant to the 1738 Treaty of Vienna that ended the war , France eventually withdrew from Kehl and Philippsburg , but eventually annexed Lorraine .