The siege of Poitiers (27 July-7 September 1569) was an unsuccessful Huguenot attempt to capture the wealth city that cost them over 2,000 dead before the Royal army lifted the siege.
1569 began with a Catholic victory at Jarnac (13 March 1569) at which the Prince of Condé, one of the main Huguenot leaders, was killed. The Catholics had then gone on to besiege Cognac, where they suffered as many casualties as the Huguenots had at Jarnac. While this siege was underway the Protestants received reinforcements from Germany, and won a minor victory at La Roche-Abeille (25 June 1569).
Both sides now had to decide what to do next. In the Royal camp a council of war decided to disband most of the army for a short period, partly to allow their volunteers to return home for a time and partly because they believed that the Huguenot army might begin to collapse without an obvious opponent.
In the Huguenot camp Admiral Coligny, now the leading figure, wanted to attack Saumur in order to secure the lines of communication between La Rochelle and the Huguenots in the north, but most of the leaders preferred to attack Poitiers, then one of the richest cities in France.
The Huguenot army appeared outside Poitiers on 24 July, and the formal siege began on 27 July. The defence of the city was commanded by the Comte de Lude, but the city also contained Henry, duke of Guise, soon to become one of the main figures in the Wars of Religion, and his brother Charles, duke of Mayenne, who would become one of the last figures to oppose Henry IV as the wars finally came to an end.
Coligny chose to focus his attention on the eastern side of the city, where the defences were overlooked by high ground, but this mean that the attackers would have to cross the River Clain. The Huguenots had a small amount of artillery during this siege, and were able to make a break in the east wall of Poitiers, but the defenders were able to destroy the bridge they threw across the river.
The Huguenots were made to suffer for their choice of camp when the defenders dammed the river. The resulting lake flooded the Huguenot camp, and disease was rife. Even Coligny was taken ill.
At the start of September Coligny turned his attention to the suburb of Rochereiul, at the south-west of the city and undefended by water. Once again a breach was made in the wall, and a three-part assault was launched on 3 September. The Duke of Guise began to make his name during this assault, fighting in the breach and played a part in the defeat of the assault.
Time was now running out for the Huguenots. The Duke of Anjou (with Tavanne in real command) had reassembled his army, and early in September moved to threaten the Huguenot-held city of Châtellerault. The threat was too serious to be ignored, and on 7 September Coligny lifted the siege. During the seven weeks that the Huguenots had been outside Poitiers they had suffered around 2,000 dead, while the defenders had only lost 300-400. The Royal commanders had been provided right in their belief that the Huguenot army would begin to fade away, although perhaps not for the right reasons.
After leaving Poitiers Coligny moved to lift the siege of Châttellerault. Anjou retreated, having achieved his main objective. Coligny then decided to move into southern Poitou, where he could join up with the Army of the Viscounts, a Huguenot force that had just won a series of victories in Bearn. Anjou managed to intercept the Huguenot army, winning a major victory at Moncontour on 3 October 1568.