1066: The Year of the Conquest
— David Howarth

Although it reads like a novel, there's a lot of history packed into this book. The story describes the happenings of the year in which William the Conqueror invaded England -- an event of the early Middle Ages which had far-reaching implications for both knighthood and Western culture.

The Conquering Family
The Last Plantagenets
The Three Edwards
— Thomas B. Costain

These three history books, which shed light on England from the 11th to the 14th centuries, have the benefit of being written by a talented novelist. The author provides enjoyable language and brisk pacing to keep the historical details from becoming too dreary.

The Hundred Years War
— Robin Neillands

This book demonstrates two things: First, that the truth is stranger than any fiction, and second, that some historians do have a sense of humor. The author clearly appreciates the wry ironies and quirky personalities behind the extensive conflict between England and France. (If you're a Shakespeare fan, this book is a great way to discover some of the real-life events and characters you'll see in the Bard's history plays.)