In January of 1204 a mysterious message is delivered to the covenant:
To the order of Hermes, withdraw yourselves and your church from these lands. The traitor Haakon III, who sought peace with your Church, now lies dead, and others who stand against the religious sovereignty of Norway shall find themselves likewise.
Upon receiving the note, Hugh first casts a spell to check for active magics. If he senses none, he casts again, this time scrying to see the room around whomever wrote the note.
The letter is a link to the writer, not the room, so the room cannot be the target. In this case however it appears that whatever arcane connection there was has faded.
Assuming there is no obvious way to return correspondence, I don't see any further action. Hugh will ask someone that speaks Norse to ask around the covenfolk if they know of any way to contact the Order of Odin; and make sure there is no Christian iconography present in the covenant.
"Greetings, Heimdall. As usual, we're her to see you, not to pass. We've received a message from Order of Odin and we were wondering if you could tell us anything about them."
"The followers of Odin have been a part of this land for as long as I can remember..."
What follows is an hour long monologue about various followers and cults following Odin over the last thousand years or so.
There are a couple of factions that were discussed which might fit the bill, but it is hard to be certain. Also of interest to Hugh was the faction of Odinists who went to Greenland and Vinland...
" Over 2 centuries ago, when Lief Erickson had disappeared to the west of Greenland, the diviners of the Vikings sought answers as to where he had gone, and then did might Odin decree that nothing should be revealed to them, and none might speak to mortals of the lands beyond the western sea, lest more attempt the journey and possibly rouse Jörmungandr to action."
"The man who delivered the message was given it by a hooded figure in the town of Filefjell, where the King is building a church over an ancient temple. I would suggest you begin your search there."