However, Gauls of the Boii and Insubre tribes in northern Italy attacked the Roman colonies of Placentia and Cremona, causing the Romans to flee to Mutina, which the Gauls then besieged. Praetor L. Manlius Vulso marched from Ariminium with two Roman legions, 600 Roman Horse, 10,000 allied infantry and 1,000 allied cavalry towards Cisalpine Gaul.
However, tribes of the Boii and Insubre in northern Italy launched attacks on Roman colonies in Placentia and Cremona, prompting the Romans to retreat to Mutina, which was then besieged by these Gauls. The Roman commander L. Manlius Vulso led two legions, 600 Roman Horse, 10,000 allied infantry, and 1,000 allied cavalry from Ariminium towards Cisalpine Gaul.