This is the second in the King’s Hounds series, named after the main characters Halfdan and Winston, who have been taken into the confidence of King Cnut, the Danish conqueror of England. They solved a murder and saved his bacon in the first book, and now they’re back for another interesting medieval murder mystery.
Halfdan and Winston are traveling north to see how everything is going up there, to be the King’s eyes and ears. On the way, they stay at a monastery. A monk is murdered, and they are asked to stick around and solve the crime. Like all monasteries, there is a collection of crazies and power-mad monks, along with a normal person or two.
There’s a lot going on in this book, with flashbacks to the war and some horrible atrocities that took place before the Danes finished conquering England – and everything ties together somehow.
Apparently this is based on an actual incident that Jensen learned about when he was on a research trip to England – basing his stories on actual events (while clearly imagining the details) makes the stories more compelling to me. The Oathbreaker of the title is a real doozy, and makes for an exciting conclusion to another great mystery.