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 1235 Emperor Frederick was in Germany to quell 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 August 1237 the emperor returned again to Italy, this time aiming to definitively 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 for most of the Lombard League troops to reach Brescia. The 2,000-knights and 6,000-infantry strong army, led by Pietro Tiepolo, podestà of Milan and son of the doge of Venice, 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 more 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 rumors, skilfully spread by the emperor, that he was withdrawing to Cremona to spend the winter there.