The Battle of Brignais was fought on the 6th of April 1362, between forces of the Kingdom of France under Count Jacques de Bourbon, from whom the later royal Bourbons descend, and the Tard-Venus Free Companies, led by mercenary captains including Petit Meschin and Seguin de Badefol.

When Petit Meschin (who was during that time pillaging the nearby County of Forez) learned that his comrades where in trouble, he brought his men back to Brignais as fast as he could.

Then, taking advantage of the heights, the night, and the element of surprise, he charged against the royal army's camp.

The garrison inside the castle then joined Petit Mesquin's forces, resulting in a total defeat for the French army.

According to Jean Froissart, Seguin de Badefol had the idea to dispatch the Tard-Venus forces into two groups: one in front of the royal army, and the other one on surrounding hills.