John II and his family were steadfast supporters of the English cause among the French nobility, and his brother Louis (1391–1443), the bishop of Thérouanne, became chancellor of France for the Duke of Bedford.

Guise, at that time the last Armagnac outpost in northern France,[3] was of strategic importance grew due to its position between Burgundy and the Burgundian Netherlands.

John II was a descendant of the Châtillon counts of Saint-Pol, who formerly held Guise, and his claim to it was recognized by the Duke of Bedford.

Joined by an English force under sir Thomas Rempston, John II put the city under siege, and Guise, along with the fortress of Hirson, formally surrendered to him on 1 March 1425.

In early 1436, Ligny was asked by Duke Philip III to help reach a peace agreement with the English, through John's older brother Louis of Luxembourg.

In late 1437, the Duke of Burgundy asked the Count of Ligny for help in raising levies for the Burgundian siege of English-held Le Crotoy.