Normandy–Brittany Border Conflicts of the 1050s

Name: Normandy–Brittany Border Conflicts of the 1050s
Start: 1051
End: 1059

Type Event Region Europe Time 1051–1059

In the 1050s, Duke William of Normandy and Duke Conan II of Brittany repeatedly clashed on the Cotentin Peninsula, around Mont Saint-Michel Bay, and …

Timeline

1054–1056Cotentin Peninsula · NormandyNorman and Breton forces raided each other along the Cotentin Peninsula border; around 1056 the two sides reached a phased truce and exchanged envoys, but the underlying territorial disputes remained unresolved.
1058–1059Mont Saint-Michel · NormandyAfter the truce broke down, the two sides fought again near Mont Saint-Michel Bay, contesting control of that strategic point and its surrounding routes; the conflict continued into the late 1050s.

Sources

Encyclopaedia Britannica: Conan II, duke of Brittany https://www.britannica.com/biography/Conan-II-duke-of-Brittany