Ever since the 4th century BCE, the Gallic tribes of northern Italy clashed with the expanding Roman Republic. In 225 BCE, the Boii forged alliances with fellow Gallic tribes of northern Italy and with tribes from across the Alps. The pan-Gallic army struck for Rome, but they were intercepted by three mighty Roman armies. Trapped at Cape Telamon, the outnumbered Gauls put up a hard fight but were ultimately defeated. The battle of Telamon marked the decline of Gallic fortunes in the war with Rome for northern Italy.
This is a companion discussion topic for the original content at https://www.worldhistory.org/article/1129/battle-of-telamon/.