The 1064–1065 animosity between Brittany and Normandy was sparked after
William the Conqueror, as Duke of Normandy, supported a Breton,
Rivallon I of Dol's rebellion against the hereditary
Duke of Brittany,
Conan II. In 1065, the year before his invasion of
Anglo-Saxon England, William of Normandy sent word to the surrounding countries (including Brittany), warning them against attacking his lands while he was away, on the grounds that his mission bore the papal banner. However, Duke Conan promptly informed the Norman Duke that he would take the opportunity to invade the latter's
Duchy.
Loss of Breton lands Duke William's army therefore set out to appease the Breton threat. While outside the monastery of
Mont Saint-Michel, two Norman soldiers became mired in quicksand.
Harold Godwinson, the
Earl of Wessex and future
King of England, saved them. (c.1066) showing Breton defenders within the castle of Dinan throwing down spears onto the Norman attackers, whilst some of the latter hold burning torches with which to burn down the wooden fortifications (d.1066) surrendering the keys (hanging from the tip of a lance) to the castle of
Dinan, to the forces of
William, Duke of Normandy, following the siege and Battle of Dinan
Battle of Dinan The Battle of Dinan occurred in 1065. Harold fought on the side of Duke William, whose army had chased Duke Conan from
Dol-de-Bretagne to
Rennes. Duke Conan finally surrendered at
Château de Dinan,
Brittany. The battle is recalled in the
Bayeux Tapestry (see illustration). ==Death of the Breton lord==