Battle of Assietta The Battle of Assietta was fought in the Italian campaign of the War of the Austrian Succession on 19 July 1747 . It resulted in a defeat for France against the army of the Kingdom of Sardinia . Background . In the late phase of the War of the Austrian Succession , France had decided to eliminate the Savoy - Piedmontese army , considered dangerous due to its strong strategic position . King Louis XV had already tried to penetrate into Piedmont , besieging Cuneo and fighting at Madonna dell ' Olmo and Bassignana . A French army comprising 150 infantry regiments , 75 cavalry squadrons and 2 artillery brigades , under the command of Marshal Charles Louis Auguste , duke of Belle - Isle , and Marquis De La Mina . The two commanders had different views on the lead of the campaign : Belle - Isle favoured a direct menace to Turin by crossing the Alps , while his Spanish colleague preferred to send troops to relieve the Austro - Piedmontese siege of Genoa . Belle - Isle ' s ideas prevailed and the French troops occupied Antibes as well as the county of Nice . However , they were halted by the strong Piedmontese defence of the southern Alpine passes . Belle - Isle ' s brother , the Chevalier de Belle - Isle , led an army of 50 infantry battalions , 15 cavalry squadrons and numerous cannon advanced towards the northern passes . The army was divided into two corps : one descended from the Moncenisio towards Exilles while the other advanced towards Fenestrelle from the Assietta Pass . The latter is a bare plateau at more than 2 , 500 meters of altitude . Although he outnumbered the French in the area 50 , 000 to 25 , 000 Charles Emmanuel III of Savoy was forced to defend all the passes into his country while the French could concentrate their force and attack one place . The decision was made to advance through Assietta . The Piedmontese had fortified the area with 13 infantry battalions : 9 Piedmontese , the remaining were Austrian and Swiss taken from the troops that had unsuccessfully besieged Genoa . French intelligence notified the marshals that the Piedmontese were fortifying the pass , and a decision to attack immediately was taken . Numerous obstacles , redoubts and a 18 foot high palisade , had been built on the slope . The forces involved amounted to 32 French battalions against 13 Piedmontese battalions . The French troops were divided into three columns with the center column pressing the attack and the flank columns failing to have much effect . The attacks began at about 16 : 30 . Despite the desperate effort of the soldiers and the personal show of valour of the French marshals , all four attacks were repulsed by the Piedmontese with heavy losses . After five hours of battle , the French retreated . The French commander , Chevalier de Belle - Isle , was killed raising the French flag near the top of the slope . What ensued in the late afternoon was celebrated as the most one - sided slaughter of the war . Neither the flanking columns moved decisively enough to influence events in . These , lashed by determined officers , the French struggled up the slope , disassembling the various man - made impediments as they proceeded , while withering musket fire from concealed and protected hideouts exacted the heavy toll . Four times the French fell back before the onslaught ; each time they returned to the struggle . The living climbed over the piles of dead as they tried to surmount the palisades . Defenders rained bullets and rocks down on the relentless blood - drenched attackers . A retreat , more orderly then the butchery , was portended The one - sided character of the slaughter was apparent - French casualties totaled , and for the first and the only times in the war the majority of them ( 3700 ) were fatalities 5 , 300 Casualties were 5 , 300 , including 7 generals , for the French ; while only 299 Piedmontese were killed and wounded . The beaten French troops returned to France . Frederick II of Prussia , after hearing of news of the Piedmontese defence at Assietta , declared that , if he had had such valorous troops , he could easily become King of Italy .