In an author's note, Frances Vernon explains that she based the central plot on events surrounding the resignation of Charles John Vaughan, Headmaster of Harrow School 1844-59, as recounted in the memoirs of John Addington Symonds, though she adds that many of the characters have undergone considerable elaboration or, in some cases, total invention. A side-plot involves the famous 1860 Oxford evolution debate between Thomas Huxley and Samuel Wilberforce concerning Charles Darwin's theory of evolution.