The battle of Jarnac (13 March 1569) was a Catholic victory early in the Third War of Religion that was notable for the death of the Huguenot leader Condé, but that had little long term impact.
In the spring of 1569 the Huguenots had two main armies in the field - the main army under Condé and Coligny around La Rochelle and a southern army, the Army of the Viscounts. In the spring of 1569 the Huguenots decided to unite these two armies, and Condé moved south from Niort and advanced to the Charente River. The Huguenots occupied Cognac and the smaller town of Chateauneuf, a little further to the east, up the river.
The main Royal army, under Henry, duke of Anjou (the further Henry III, advised by Gaspard de Tavannes) made a similar move from its winter quarters on the Loire, south towards the Charente. The Royal army crossed the river further upstream, at Ruffec, then advanced along the southern bank of the river. Chateauneuf, on the south bank, was captured, and work began to repair its bridge.
At this point the Huguenots were dangerously spread out. Coligny and the van were around Bassac, some way downstream of Chateauneuf, while Condé was even further down the river at Jarnac. Their situation began dangerous when the Royal army crossed the river undetected on the night of 12-13 March.
When Coligny belated discovered that Anjou was across the river he ordered his units to retreat back towards Condé, but it took some time for the order to reach his scattered men. In the meantime the Royal army was able to push back the Huguenot rearguard, capturing La Noue and threatening D'Andelot.
Rather than retreat back towards Condé, Coligny was now forced to send messages calling for help. Condé responded with the 300 knights at his immediate disposal, and despite having his army in a sling and a broken leg (inflicted by a kicking horse just before the battle), Condé led his men into the fray, charging a much larger Royal force. After a sharp combat Condé was isolated and forced to surrender. A few moments after this he was murdered, possibly by Montesquiou, the captain of Anjou's guards. Condé was not the only senior Huguenot leader to be captured during the battle - de la Noue, La Loue and Soubise were also taken, although survived the experience.
So far only the Huguenot cavalry had been engaged. When the infantry finally arrived on the scene it was clear that the battle was lost. This part of the Huguenot army crossed to the southern bank of the Charente and retreated to Cognac. Coligny also managed to escape from the battlefield, and retreated even further west, to Saintes.
In the immediate aftermath of the defeat the Huguenot army was understandably demoralised, but Coligny and the Queen of Navarre (mother of the future Henry IV) were able to restore morale. Anjou helped with an unsuccessful siege of Cognac, and the war continued.