The Sea's Edge (The Atheling Chronicles, #4)

1030 C.E.: Harald, the second son of King Cnute—ruler of Engla-lond, Danmark, and Norvegr—with his wife Selia, attempt to live as landholders in Mercia, away from the constraint and intrigues of his father's court.

However, on a rare visit, Cnute tells Harald he's being sent to the Kingdom of Dublin to meet with their Norse-Irish allies. Harald's mission is to coordinate an invasion of the northern Welsh kingdom of Gwynedd to replace King Rhydderch who is growing too powerful on England's bo...