This in the final book I had read in the Pendragon Cycle, back in the day (aka, high school). It was also formerly the last book in the cycle – and it’s very much an end book, so it would appear that the two books that come after it take place in time frames covered by this book, as this book starts with Arthur taking the sword from the stone, and ends with him going to Avalon, gravely wounded, after the battle with Medraut.
These books have always taken their own path through Arthurian legend – Arthur is the son of Aurelius, not Uther; when he takes the sword from the stone, the other kings will not immediately accept his High Kingship, so he takes up Uther’s old title of Duke of Britain instead; Gwenhwyvar is an Irish queen (in her own right) and warrior – I could go on.
As I’ve noted in my rereads of the previous two books in the series, this is also a very Christian book. Again, perhaps not in a modern way that would tie into any particular flavor of Christianity of our time, but it’s a contrast to many other modern retellings where the struggle between the pagan religions and Christianity coming in is much more pronounced.
The other thing about this book it’s very compact compared to the other two. I think that’s partially because the other two really do deal with the life of particular person (or two – Charis and Taliesin, and Merlin), and while this book focuses on Arthur, it’s about more than just him – it’s the whole Summer Kingdom. I suspect that’s why the author chose to expand the series. And now I’ve tracked those two books down (as well as a sixth book – Avalon, which is apparently a modern day postscript). So I’ll be out of reread territory, and into something new.