As a devotee of Roman history I have, of course, been long familiar with the story of Hadrian - or at least, I thought I was. "Following Hadrian" demonstrated to me that while I was familiar with the bare bones of his story, I had not fully grasped the significance of his life and times. As the author makes clear, there is a great deal more to Hadrian than his role as the consolidator of the Roman Empire in the early second century and, pereversely, a great deal less. What Elizabeth Speller gives the reader is not a simple account of the Emperor's political significance, but also a much wider understanding of him as a man. By giving a great deal attention to his relationsip with Antinous, something that many historians simply skate over, she adds a dimension to Hadrian's story that makes our understanding of him far more complete.
I do have a quibble, however, that many readers might categorise as "nit-picking," but which I believe undermines the work to a certain extent. By including an entirely fictitious memoir of Julia Balbilla, the author speculates on Hadrian's motives and actions as if she is presenting evidence. At one point "Julia Balbilla" tells us that, if there was anything suspicious in the death of Antinous, then neither she nor the Emperor's wife, Sabina, had anything to do with it. There might be good reason for believing this, but, if so, the author undermines her case by by using a fictional device rather than by presenting straightforward historical evidence. To me the "memoir," though well-written, is simply a distraction from an otherwise excellent piece of work.