The Once and Future King series, about King Arthur from boyhood to the bitter end, by T.H. White.http://www.bookreporter.com/authors/author_bibliographies/li-robb-jd.asp
It is extremely well-written, imaginative, even funny.
The first book, The Sword in the Stone is reviewed here in Wikipedia.
“The book begins as a quite light-hearted account of the young Arthur’s adventures, Merlin’s incompetence at magic, and King Pellinore’s interminable search for the Questing Beast.
Parts of The Sword in the Stone read almost as a parody of the traditional Arthurian legend by virtue of White’s prose style, which relies heavily on anachronisms. However, the tale gradually changes tone until Ill-Made Knight becomes more meditative and The Candle in the Wind finds Arthur brooding over death and his legacy.”