Jean de la Brosse, Marshal of France, is sometimes called Marshal de Boussac and Marshal de Saint Sévère, from the names of his fiefs. He commanded the guard of a hundred men who were the special bodyguard of the King. He distinguished himself at Orléans and at Patay, attended the coronation of Charles VII at Reims, and was appointed the King's lieutenant beyond the Seine, Marne and Somme.

On June 5, 1430, Charles VII announced to the people of Reims that he was going to give prompt aid to the town of Compiègne. It was a question of Boussac's coming: he was in command of a column of wagons following the army of Saintrailles an Vendôme which delivered Compiègne on October 25. We find de Boussac later in the army which offered combat to Burgundian troops at Montdidier in November.

On February 3, 1432, a troop of six hundred French under his command approached Rouen secretly, planning to take the city by scaling the wall at night. Jean de la Brosse died in 1433. deliverance of Jeanne d'Arc from Rouen. But he was captured by the Burgundians who held him for a ransom of 1,500 réaux d'or and kept him prisoner at Dourdan. In September, 1432, La Hire appeared at Lagny, which was besieged by Bedford, and he ravaged the lands of the Duke of Burgundy around Cambrai the following year. Captain general of the hither side of the Seine, in December, 1433, he took Ham and Breteuil from the Burgundians and defeated the Earl of Arundel at Gerberoy (1435).

In spite of the peace of Arras he continued to wage guerrilla warfare in Artois, around Caux, but he was taken prisoner by the Lord of Offémont at Beauvais (1437). In the service of René d'Anjou, La Hire led the Écorcheurs in Lorraine (1438-1439). He took part in the sieges of Harfleur and Pontoise, and in the battle of Tartas.

He died, poor and glorious, at Montauban on January 12, 1443.