Desmond Steward "The Demon's Brood: The Plantagenet Dynasty That Forged the English Nation" (Constable)

This is a conservative, schoolbook-ish chronological history of the Plantagenet dynasty, from Henry II to Richard III. Seward has an intensely dry, academic sense of humour which sometimes comes through in his strong opinions about other historians, and he has a good eye for an anecdote. He's also clearly one of those people who thinks that suggesting a historical figure might have had a homosexual relationship is slander, and he's never heard of a bisexual (or, indeed, of the fact that pre-modern sexualities were very different than modern ones). A decent introduction, if you need one, to the basic events of the period but if you want a meatier introduction to the period there are better books around.