Roger of Mortemer

Roger I of Mortemer (Roger de Mortemer, Roger de Mortimer, Roger Mortimer) (bef. 990 - aft. 1078), founded the abbey of St. Victor en Caux in the Pays de Caux of Upper Normandy as early as 1074 CE. Roger claimed the castle built by his kinsman William FitzOsbern, 1st Earl of Hereford, that was situated on the river mouth of Eaulne in Mortemer, Seine-Maritime. This castle was the chief barony of Roger's descendants. He was the first Norman ancestor to assume the name Mortimer, as in the place-name Morte-mer-en-Brai, the land on which the village and castle was located.

In 1054, the territory of Évreux was invaded by French armies led by Odo, the brother of King Henry I of France. In response, Duke William II of Normandy sent his general Roger "fili Episcopi", along with other commanders, to oppose Odo’s forces. They met at the castle in Mortemer, Seine-Maritime where the battle of Mortemer ensued. Roger was victorious against Odo, with Guy Comte de Ponthieu taken prisoner. Roger then took possession of the castle in Mortemer and assumed its name. However, his hold on the property was short lived due to a breach of duty to Duke William. Roger had entertained an enemy of the Duke, who was a French operative known as Count Ralph III “the Great”. Count Ralph was Roger’s father-in-law, and thus gave the Count shelter for three days at his castle in Mortemer until he was able to safely return to his own territories. Upon discovering the news that Roger was providing safe haven for an enemy, Duke William banished Roger from Normandy and confiscated his possessions, giving them to his nephew, William de Warenne. Eventually, Roger was pardoned by the Duke, but was never able to retain the castle in Mortemer. It wasn’t until Roger’s son, Ranulph de Mortemer, was able to repossess the property by grant of Duke William. He is last seen in a document dated between 1078 and 1080.

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