Treaty of Rouen (991)

It tells us that, having ‘been informed by many of the enmity between Ethelred, King of the West Saxons, and Richard the marquis [Duke of Normandy]’, Pope John XV had decided to send his legate, Bishop Leo of Trevi, to rectify this breakdown of relations.

[2]While the letter indicates that the pope had intervened in this matter due to hostilities between the English king and the Duke of Normandy, it is not clearly stated what had caused these troubles.

[3] The historian Eric John believes that the end of the papal letter, which states that neither man should receive the enemies of the other, is clearly prohibiting the use of Norman ports as a viking base.

[5] In this case, it is likely that the pope decided to intervene in order to remind Richard that it was unacceptable to aid pagans who pose a threat to his fellow Christians.

[4] The historian Jenny Benham contested this theory, as much of the evidence which relates to vikings being given entry to Norman ports is written after this letter from Pope John XV.

William of Jumièges wrote in the 1050s of an English attack on the Cotentin in Normandy: this probably occurred sometime between 1000 and 1002, and seems to have been a response to Richard's harbouring the raiders.