First Notes on 'Memoirs of Hadrian'

Herbert W. Benario, in Hadrian (DIR), comments on the novel that

 [Yourcenar] presents a Hadrian as he might have been, and, although she commands a wide range of source material, the reader must always be alert to the fact that this Hadrian is not necessarily the historical Hadrian.

The above web page is appended by Historians and their Craft: The Evolution of the Historical Hadrian by Andrew Hill, which gives an excellent overview of how Hadrian was seen from Gibbon to the present.

The article comments favorably on Anthony Birley's Hadrian : The Restless Emperor (London: Routledge, 1997). I certainly find the book a very interesting and illuminating read.

Birley himself says more strongly than Benario that Yourcenar's Hadrian is a different person than the historical one, but he praises her "intuition and literary genius."