Battle of Ulm The Battle of Ulm on 16 – 19 October 1805 was a series of minor skirmishes at the end of Emperor Napoleon ' s Ulm Campaign . It culminated in the surrender of Karl Freiherr Mack von Leiberich and a significant part of his army near Ulm in Württemberg . Background . In 1805 , the United Kingdom , the Austrian Empire , Sweden , and the Russian Empire formed the Third Coalition to overthrow the French Empire . When Bavaria sided with Napoleon , the Austrians , 72 , 000 strong under Mack , prematurely invaded while the Russians were still marching through Poland . The Austrians expected the main battles of the war to take place in northern Italy , not Germany , and intended only to protect the Alps from French forces . A popular but apocryphal legend has it that the Austrians used the Gregorian calendar , the Russians were still using the Julian calendar . This meant that their dates did not correspond , and the Austrians were brought into conflict with the French before the Russians could come into line . This simple but implausible explanation for the Russian army being far behind the Austrian is dismissed by scholar Frederick Kagan as " a bizarre myth " . Napoleon had 177 , 000 troops of the Grande Armée at Boulogne , ready to invade England . They marched south on August 27 and by September 24 were ready to cross the Rhine from Mannheim to Strasbourg . After crossing the Rhine , the greater part of the French army made a gigantic right wheel so that its corps reached the Danube simultaneously , facing south . On October 7 , Mack learned that Napoleon planned to cross the Danube and march around his right flank so as to cut him off from the Russians who were marching via Vienna . He accordingly changed front , placing his left at Ulm and his right at Rain , but the French went on and crossed the Danube at Neuburg , Donauwörth , and Ingolstadt . Unable to stop the French avalanche , Michael von Kienmayer ' s Austrian corps abandoned its positions along the river and fled to Munich . On 8 October 1805 , Franz Auffenberg ' s division was cut to pieces by Joachim Murat ' s Cavalry Corps and Jean Lannes ' V Corps at the Battle of Wertingen . The following day , Mack attempted to cross the Danube and move north . He was defeated in the Battle of Günzburg by Jean - Pierre Firmin Malher ' s division of Michel Ney ' s VI Corps which was still operating on the north bank . During the action , the French seized a bridgehead on the south bank . After first withdrawing to Ulm , Mack tried to break out to the north . His army was blocked by Pierre Dupont de l ' Etang ' s VI Corps division and some cavalry in the Battle of Haslach - Jungingen on 11 October . By the 11th , Napoleon ' s corps were spread out in a wide net to snare Mack ' s army . Nicolas Soult ' s IV Corps reached Landsberg am Lech and turned east to cut off Mack from the Tyrol . Jean - Baptiste Bernadotte ' s I Corps and Louis Nicolas Davout ' s III Corps converged on Munich . Auguste Marmont ' s II Corps was at Augsburg . Murat , Ney , Lannes , and the Imperial Guard began closing in on Ulm . Mack ordered the corps of Franz von Werneck to march northeast , while Johann Sigismund Riesch covered its right flank at Elchingen . The Austrian commander sent Franz Jellacic ' s corps south toward the Tyrol and held the remainder of his army at Ulm . Battle . On 14 October , Ney crushed Riesch ' s small corps at the Battle of Elchingen and chased its survivors back into Ulm . Murat detected Werneck ' s force and raced in pursuit with his cavalry . Over the next few days , Werneck ' s corps was overwhelmed in a series of actions at Langenau , Herbrechtingen , Nördlingen , and Neresheim . On 18 October he surrendered the remainder of his troops . Only Archduke Ferdinand Karl Joseph of Austria - Este and a few other generals escaped to Bohemia with about 1 , 200 cavalry . Meanwhile , Soult secured the surrender of 4 , 600 Austrians at Memmingen and swung north to box in Mack from the south . Jellacic slipped past Soult and escaped to the south only to be hunted down and captured in the Capitulation of Dornbirn in mid - November by Pierre Augereau ' s late - arriving VII Corps . By 16 October , Napoleon had surrounded Mack ' s entire army at Ulm , and three days later Mack surrendered with 30 , 000 men , 18 generals , 65 guns , and 40 standards . Some 20 , 000 escaped , 10 , 000 were killed or wounded , and the rest made prisoner . About 6 , 000 French were killed or wounded . At the surrender ( known as the " Convention of Ulm " ) , Mack offered his sword and presented himself to Napoleon as , " the unfortunate General Mack . " Under the treaty Bonaparte smiled and replied , " I give back to the unfortunate General his sword and his freedom , along with my regards to give to his Emperor " . Francis II was not as kind , however . Mack was court - martial ed and sentenced to two years ' imprisonment . The Ulm Campaign is considered one of the finest examples of a strategic turning movement in military history .