The engagement was part of Prince Eugene of Savoy's campaign to seize the Spanish controlled Duchy of Milan in the Italian peninsula, and had followed his victory over Marshal Catinat at the Battle of Carpi in July.

Marshal Villeroi replaced Catinat as commander of the Franco–Spanish–Savoyard forces in the theatre, carrying with him orders from King Louis XIV to push the Imperialists out of Italy.

[7] Villeroi joined the army, and his generals – the Duke of Savoy, Catinat, and the Prince of Vaudémont – and marched to find the enemy, confident he would drive them from Italy.

But the French, whose camp was built on marshy ground, suffered most, and they moved out first in mid-November, crossing the Oglio before entering winter quarters in the Duchy of Milan.

[11] For his winter quarters Eugene proceeded to reduce the whole Duchy of Mantua, except the capital and Goito, which he closely blockaded; shortly after he occupied Mirandola and Guastalla.

[9] Eugene's relationship with the local population had been good and he had kept a tight control: he had executed 48 of his men for looting, telling the Emperor that he had 'imposed more severe discipline than has possibly ever been seen in an army'.

[11] Eugene had received little cash from the Emperor, far less than he expected, but he had secured a sound footing in northern Italy and, as hoped, his success helped to encourage the Maritime Powers to come to the aid of Leopold I.

With Eugene's two victories (Carpi and Chiari), Leopold I had proved he would fight to protect his interests, giving Wratislaw the arguments he needed to push through the alliance with the Maritime Powers.

[12] On 7 September 1701 – within a week of the battle – England and the Dutch Republic signed the second treaty of the Grand Alliance, backing the Emperor's claims to the Spanish possessions in Italy.