The Seventh War of Religion (1580) was the least significant of the nine wars of religion, and saw Henry of Navarre expand his influence in the south-west of France.
After the end of the Sixth War of Religion France remained in a state of turmoil. Many of the terms of the peace of Bergerac were never implemented, and this came close to triggering a return to war. In November 1579 the Prince of Condé seized La Fère, which was meant to have been handed over to him in his new role as governor of Picardy, and Henry III was only narrowly persuaded not to declare war.
When open war did come, for once it was the Huguenots who began it. Henry of Navarre wrote a long letter justifying the new war, using the excuse that the terms of the peace of Bergerac were being ignored. However many people believed that the real cause of the war was the hostility between Navarre’s wife Margaret of Valois and her brother Henry III. Margaret was even said to have used her husband’s mistresses to help convince him to declare war. Many parts of Margaret’s dowry had yet to be delivered, and this played a part in the course of the brief war. As a result the war was known a the time as the ‘Lover’s War’, and when the call to arms went out on 15 April 1580 only about a third of the Huguenots responded.
The most significant fighting came at Cahors, which had been promised to Margaret as part of her dowry. Henry of Navarre attacked the town, which fell after several days of street fighting (siege of Cahors, 28-31 May 1580)
Elsewhere the Royal armies were more successful. In September Marshal Matignon besieged and captured La Fère, which fell while Condé was absent in Germany recruiting troops. Armies under the duke of Mayenne and Marshal Biron were also successful. This helped convince Navarre to enter into peace negotiations, at the castle of Fleix in Perigord. The resulting peace of Fleix was virtually a re-issue of the Peace of Bergerac, and this time led to five years of relative peace in France, which only ended when Anjou died, leaving Henry of Navarre as heir to the throne. This caused a crisis that triggered the Eighth War of Religion (1585-89), or the War of the Three Henrys.