Battle of Cortenuova The Battle of Cortenuova ( sometimes spelled Cortenova ) was fought on 27 November 1237 in the course of the Guelphs and Ghibellines Wars : in it , Holy Roman Emperor Frederick II defeated the Second Lombard League . Background . In 1236 Emperor Frederick was in Germany to quench the rebellion of his son Henry . In the autumn of that year he decided to return to Italy to suppress the Lombard communes which , backed by Pope Gregory IX , were contesting his authority . He arrived at Valeggio , near Verona , and , with the help of Ezzelino III da Romano and other Ghibelline leaders , sacked the city of Vicenza . Satisfied with this first outcome , he came back to Germany to deal with another German princes rebellion , leaving Hermann von Salza , Grand Master of the Teutonic Order , in Italy to monitor the situation . In the August 1237 the emperor returned again to Italy , this time aiming to definitely crush the Second Lombard League . He crossed the Alps to Verona and here his 2 , 000 knights were joined by Ezzelino III da Romano ' s troops , including soldiers from Treviso , Padua , Vicenza and Verona itself , as well as by Tuscan men led by Gaboard of Arnstein . Later 6 , 000 infantry and horsemen from the Kingdom of Sicily came , including Apulian Muslim archers . The rest of the army was formed by Ghibellines from Cremona , Pavia , Modena , Parma and Reggio , for a total of 12 , 000 - 15 , 000 men The imperial army marched first against Mantua , which decided to surrender instead of being sacked and then to Bergamo , whose council of nobles took the same decision in exchange for no formal submission . Frederick then invaded Brescia ' s territory , capturing Goito and Montichiari among the others , although the latter ' s resistance gave time to most of the Lombard League troops to reach Brescia . The 2 , 000 - knights and 6 , 000 - infantry strong army , led by Pietro Tiepolo , son of the doge of Venice and current " podestà " of Milan , occupied a favorable position at Manerbio ( November 1237 ) . The two armies remained fifteen days facing each other without battling , separated by a marsh that thwarted the knights ' effectiveness . Frederick , whose army was becoming short of supply , left his camp in search of a most advantageous position , and on 24 November 1237 crossed the Oglio river , marching northwards to wait for the enemy ' s moves at Soncino . The battle . The Lombards believed the voices , which had been skilfully spread by the emperor , that he was retreating to Cremona to spend the winter there . Therefore , they also left the field , returning to their quarters . Frederick had however attested a contingent from Bergamo at Cividate al Piano , which would inform him of the Lombard retreat through smoke signal s . When the Lombard army had completed its crossing of Oglio at Pontoglio and Palazzolo , the imperial troops saw large smoke clouds and moved to Cortenuova , which was 18 km from their current positions . The imperial vanguard included Saracens and horsemen , which were the first units to attack the Lombard units , followed by the infantry . Taken by surprise , the Milanese and Piacentines were unable to form a defense line , and fled to Cortenuova . When Frederick and his main force reached the battlefield , it was scattered with knights , slain or wounded and his passage blocked by riderless horses . At Cortenuova , other Milanese and troops from Alessandria had amassed around their Carroccio , where the Lombards fought valiantly under the Saracen arrows and the Teutonic charges . A column of men from Milanese noble families , despite the arrival of other Bergamo troops , was able to protect the rest of the army ' s retreat to Cortenuova till night . To keep the army ' s morale as high as possible , Frederick ordered his troop to sleep with their armors on , and to attack at the first lights of dawn . On the other side , the " podestà " of Milan , recognizing that the troops could not withstand another battle , ordered to abandon the town together with the Carroccio and the rest of the baggage . On the dawn of 28 November the imperial attacked the hastily retreating Lombards , who fell without nearly no resistance . Many drowned in the Oglio , which was in spate . At the end , some 5 , 000 Lombards were captured , casualties amounting to some other thousands killed . The Milanese alone lost 2 , 500 soldiers Of the battlefield , Pietro della Vigna recorded : Aftermath . The Lombard League ' s army was virtually annihilated . Frederick made a triumphal entrance in the allied city of Cremona , with the Carroccio towed by an elephant and Tiepolo chained on it . The latter was first detained in Apulia and then publicly executed in Naples . The Carroccio was later sent to Rome as a show of the imperial power . The Lombard League disbanded . Lodi , Novara , Vercelli , Chieri and Savona were captured or submitted to the emperor , while Amadeus IV of Savoy and Boniface II of Montferrat confirmed their Ghibelline allegiance . Milan , Brescia , Piacenza and Bologna remained alone in Arms . Frederick , now at the top of his strength , besieged Milan . He rejected all Milanese peace overtures , insisting on unconditional surrender . Milan and five other cities , however , held out , and , in October 1238 , he had to raise the siege of Brescia . The emperor then went on to invade the Papal States , and was excommunicated by Pope Gregory IX .