Key Facts
- Duration
- ~16 months (1449–1450)
- War declared
- July 31, 1449
- Decisive battle
- Battle of Formigny, spring 1450
- Final English stronghold fell
- Cherbourg, August 12, 1450
- Trigger event
- English capture of Fougères, March 1449
Strategic Narrative Overview
The campaign unfolded on two simultaneous fronts during summer and autumn 1449: French royal forces advanced through Upper Normandy while Breton troops pushed into the Cotentin Peninsula. In spring 1450 the two armies combined and delivered a crushing blow to the English at the Battle of Formigny. This defeat shattered English field strength in the region and exposed the remaining garrison towns to capture.
01 / The Origins
The campaign was triggered when English forces broke the Treaty of Tours by seizing the Breton town of Fougères in March 1449. France and the Duchy of Brittany responded by concluding an alliance and formally declaring war on England on July 31, 1449. The action gave France a pretext to pursue the systematic recovery of Normandy, a duchy England had held since Henry V's conquest decades earlier.
03 / The Outcome
Following Formigny, French and Breton forces systematically reduced the surviving English-held towns. Caen fell, and Cherbourg, the last English stronghold in Normandy, surrendered on August 12, 1450, ending English territorial presence in the duchy. The victory freed the French crown to redirect military resources southward, ultimately enabling the conquest of Bordeaux in 1453 and the close of the Hundred Years War.
Belligerents & Mobilization Analysis
Side A
1 belligerent
Side B
2 belligerents
Kinetic Engagement Axis
Scroll horizontally to view full axis. Events plotted relatively.