Siege of Philippsburg ( 1734 ) The Siege of Philippsburg was conducted by French forces against forces in the fortress of Philippsburg in the Rhine River valley during the War of the Polish Succession . The Duke of Berwick led 100 , 000 men up the Rhine Valley in opposition to Austrian forces , of which 60 , 000 were detached to invest the fortress at Philippsburg , beginning on 1 June 1734 . A relief column of 35 , 000 under the aging Prince Eugene of Savoy ( accompanied by Crown Prince Frederick of Prussia ) was unsuccessful in actually relieving the siege . On 12 June Berwick was killed by a cannonball while inspecting the trenches , and command of the besiegers fell to Marshals d ' Asfeld and Noailles . The fortress surrendered one month later , and the garrison withdrew to the fortress of Mainz with the honours of war . D ' Asfeld was promoted to Marshal of France for his role in the campaign ; Wuttgenau was promoted to lieutenant general for his spirited defense of the fortress . Background . 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 King Louis XV of France . Whilst a body double ostensibly left Brest by sea , Stanislas 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 , both of whom backed 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 , protected by 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 the Duke of Milan wanted , 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 , Duke of Berwick to form an army for invading the Rhineland with the objectives of gaining the Duchy of Lorraine and distracting Austria from events in Poland . In the fall of 1733 the French army crossed the Rhine and besieged Kehl , near Strasbourg . Although they captured and occupied the fortress , most of the army was withdrawn to the west bank of the Rhine due to the onset of winter in December . During the winter , Austrian field marshal Prince Eugene of Savoy began gathering forces of the empire at a camp near Heilbronn to oppose the French . By the spring of 1734 these forces were still significantly smaller than those of France , which had nearly 70 , 000 men in the field . Freiherr Gottfried Ernst von Wuttgenau was given command of the fortress at Philippsburg in December 1733 . The fortress was in deplorable condition , and its moat had in places been filled to the point where the ramparts could easily be approached . He focused defensive preparations on the fortress ' flood controls , a significant defense against besiegers who were required to work in the swampy terrain below the fortress , while his engineer , Gerhard Cornelius von Walrave , directed repairs and improvements to the fortress ' eastern works , where attacks had been focused in the past . By the spring of 1734 these preparations were largely complete , although the garrison was short of ammunition and experienced artillery personnel and engineers . The defenders consisted of a battalion of Walseggers , companies from the Kaiser ' s regiments of Württemberg , Max Hessen , Kettler , Müfflingen , Sachsen - Gotha , Wolfenbüttel , Walsegg , and Bevern , the Frankish Höltzl regiment , and companies from the Frankish Bassewitz and Heller regiments . Siege . In late May 1734 , the French began surrounding the fortress at Philippsburg . A total of 46 battalions were deployed , with 14 on the left bank of the Rhine , and the balance on the right bank , cutting the land approaches to the fortress . Of the troops on the right bank , half were dedicated to the siege , while the rest were detailed to defend the siege camp against any attempts to relieve the siege . On May 26 they began digging the outer trench surrounding the fortress with a complement of 12 , 000 men . The siege works progressed under Berwick until June 12 , when he was felled by a lucky shot while examining siege works at a forward position . Command of the besieging army then came to d ' Asfeld . On June 19 , Eugene , under orders from the Kaiser , began moving his army , which had since grown to over 70 , 000 men , toward Philippsburg with the goal of relieving the siege . On June 27 the army reached Bruchsal . D ' Asfeld responded by building additional boat - bridges over the Rhine to speed the movement of cavalry across the river , and redirected some of the siege personnel to face Eugene ' s threat . The French position was further inconvenienced when heavy rains on July 5 caused portions of their position to be flooded . Despite these difficulties , Eugene failed to act decisively to capitalize on the situation , and withdrew his army . By July 17 the French had penetrated the fortress ' defenses to its inner moat , and were threatening the heart of the fortress . After failing to establish contact with Eugene , Wuttgenau and d ' Asfeld agreed to terms of capitulation early on July 18 .