I really enjoyed this book, which seems like the sort of book that will be worth re-reading. Ursula K. Le Guin is quoted on the cover as saying "I have laughed at [this] great Arthurian novel and cried over it and loved it all my life."
I liked the first book, which was about Wart growing up with Merlyn as his teacher and how he becomes King Arthur, the best. The second book, The Queen of Air and Darkness, is mostly about the forming of the round table and a lot about the Orkney clan. It includes a lot of ancient history of what becomes Great Britain. Book three is Lancelot's story, The Ill-made Knight, and was my least favorite. The final book, The Candle in the Wind, tells us about what happened as Arthur and his friends and enemies get older and a younger generation comes into its own.
The tone of the book is very irreverent in places and makes the story entertaining. White frequently refers to other tellings of the Arthurian legends, especially Malory's Le Morte d'Arthur, and is often funny about it. At several points he says basically that there is a long boring bit here about a battle (or a procession, or whatever) and if you want to know all the gory details go read Mallory. Here is a passage that I loved and that I think is a good representation of the style of the first book (The Sword in the Stone):
"There was a real corkindrill hanging from the rafters, very life-like and horrible with glass eyes and scaly tail stretched out behind it. When its master came into the room it winked one eye in salutation, although it was stuffed. There were thousands of brown books in leather bindings, some chained to the book-shelves and others propped against each other as if they had had too much to drink and did not really trust themselves. These gave out a smell of must and solid brownness which was most secure." (p. 30)This book counts toward the What's in a Name 2014 Challenge in the category "a position of royalty."