The Second War of Religion (1567-68) was triggered by Huguenot suspicions about the intentions of Charles IX of France. The implementation of the Edict of Amboise, which had ended the First War of Religion, and had granted the Protestant Huguenots a significant amount of religious freedom, was slow and a number of changes were made to it, reducing the rights it granted.
The Huguenots were also worried by international developments. After the end of the First War of Religion Charles IX went to Rouen, where on 17 August 1663 he was declared to be of age. In the following year Charles and his mother, Catherine de Medici set off on a long progress across France, visiting a large number of towns in an attempt to curb the power of the provincial parliaments. This journey lasted until 1 May 1566 when the king finally returned to Paris. In a fateful move in 1565 Catherine met with the Duke of Alva and Philip II's queen at Bayonne, close to the Spanish border. All the evidence suggests that this was a short and inoffensive meeting, but rumours soon spread that Catherine and Philip had agreed to massacre every heretic in France and Spain.
These rumours helped to produce a state of virtual paranoia when in 1567 the Duke of Alva led a Spanish army up the Spanish Road, the land route connecting Philip's lands in Italy with the Spanish Netherlands. Alva's actual task was to put down the Dutch Revolt, which had broken out in the previous year, but many Huguenots believed that he was about to invade France to support the hard-line Catholic Henry, duke of Guise. The rumours were further fanned by Charles IX, who hired 6,000 Swiss mercenaries to guard the border against any possible Spanish move. The Huguenots feared that these troops had been hired to take part in the plot against them, and their leaders began to develop their own plot.
This plot, which became known as the 'surprise of Meaux', was essentially an attempt to seize control of the young king by force, remove the Guises from his council, and secure the Huguenot position. The 'surprise' was launched in September 1567, and came close to success, but Charles and his court managed to escape to Paris.
Condé followed the court to Paris, and at the start of October took up a position at Saint Denis, to the north of the city. This allowed him to restrict the city's food supplies, and also resulted in some unsuccessful peace negotiations. On 10 November the Royal army, under Constable Montmorency, advanced to attack the much smaller Huguenot force (Battle of Saint Denis). Condé charged the larger army, disrupted Montmorency's plans. The Constable was killed in the battle, but the Huguenot army was too small to take advantage of its early successes, and at the end of the day both sides withdrew to their camps.
Away from Paris the Huguenots were more successful. François de la Noue captured Orléans. La Rochelle, the most important Huguenot stronghold in most of the wars to come, was taken on 10 February 1568, and Auxerre, Vienne, Valence, Nimes, Montpellier and Montaubon were also taken. Perhaps most dramatic was the march of the Army of the Viscounts from Dauphiny to Orleans, defeated the Governor of Auvergne at the village of Cognac on 8 January 1568 on their way. After reaching Orleans this army reached Blois, and prepared to attack Montrichard, before being called back to take part in Condé's planned siege of Chartres. This began on 24 February 1568, but was short-lived. Peace negotiations began a few days later, and this time they were successful.
The Second War of Religion was ended by the Edict of Longjumeau of 23 March 1568, which effectively renewed the terms of the Edict of Amboise of 1563. This was a very short-lived peace, and many at the time believed that the court had never been sincere. The Third War of Religion broke out in December 1568, ended the Short Peace.