The Wanderer (Fire and Ice #5 - Michael Ridpath

Did Christopher Columbus know the Icelanders discovered America before he sailed there himself? When a young Italian tourist is found brutally murdered at a sacred church in northern Iceland, Magnus Jonson, newly returned to the Reykjavík police force, is called in to investigate. At the scene, he finds a stunned TV crew, there to film a documentary on the life of the legendary Viking, Gudrid the Wanderer.