The battle of Fontaine-Française (6 June 1595) was a minor clash between Henry IV and a Spanish army that was attempting to secure Dijon for the Catholic League (Ninth War of Religion).
After Henry IV became a Catholic many of his former opponents changed sides, but the more extreme members of the Catholic League fought on. Amongst them was the duke of Mayenne, leader of the league, whose power base was in Burgundy. However even here he was losing ground as a series of cities went over to Henry’s side. Amongst them was Dijon, where the city joined Henry, while the Citadel remained in League hands. Marshal Biron was sent to besiege the Citadel.
Mayenne gained the support of Don Juan Fernandez de Valasco, constable of Castile, Governor of Milan. In 1595 he was campaigning in the Franche-Comte, a Hapsburg possession that had once been part of the independent Duchy of Burgundy. In May 1595 Valasco entered France with around 10,000 infantry to support Mayenne, and their combined force moved towards Dijon.
Henry responded by leaving Paris on 24 May and moving south-east to Troyes, then on to Dijon, arriving on 4 June. From there he sent out probing forces to the east to find the Spanish. On 6 June part of his cavalry, under the young Marshal Biron, ran into the Spanish near Fontaine-Française, twenty miles to the north-east of Dijon. Biron didn’t realise that he had found the main Spanish army, and became engaged in a clash with Valasco’s main cavalry force. Henry rushed to his assistance, and launched a series of bold cavalry attacks on the Spanish. He was able to push back Valasco’s much larger cavalry forces, and his impetuous behaviour helped convince Valasco that the main French army must be close by. The Spanish thus failed to take their chance to capture or kill Henry and instead withdrew, much to the anger of Mayenne.
In the aftermath of this battle the Spanish withdrew back across the Saone, leaving Franche-Comte exposed to a French invasion (although Henry had to withdraw after a couple of months after his allies in Geneva made it clear that they didn’t want to conquer the area). Mayenne withdrew from the Spanish camp, and probably began the series of negotiations that saw him come over to Henry’s side early in the next year.