I'm on a Costain popular history marathon. THE THREE EDWARDS is third in the series of four about the Plantagenets. It's fairly light reading (I've been a historian, and Costain won't be on any history professor's syllabus!), but his writing is really good and the Plantagenets an intriguing bunch. He also clearly explains when he's speculating or merely repeating a good but unverifiable story about the kings and queens and their courts and coteries from centuries ago. It's a fine journey.