"In the early morning of Friday 26 April 1816," David Ellis' book begins, "Lord Byron landed in Ostend." Everyone knows what comes next: according to John William Polidori, Byron "fell like a thunderbolt on the chambermaid".
This doesn't happen in Ellis' account - at least, not until 25 pages later, because Ellis wants to supply "a more sympathetic and therefore...more accurate portrait" than recent biographical and film versions of Byron as "something of a moral monster".
His study sets out to defuse the scandal of "that summer" when, in the immediate aftermath of his separation from Annabella, Byron stayed on the shores of Lake Geneva in the company of Percy Shelley, Mary Godwin, Claire Clairmont and various other European intellectuals and exiles.
Ellis deftly sketches expatriate existence in Switzerland, presenting Geneva as a city of ironclad Calvinist rectitude that perversely became the destination of a succession of freethinking outcasts. Careful field research enables an excellent sense of Byron's locale, always uncomfortably close to English tourists who rented spyglasses from an enterprising Swiss hotelier in the hope of sighting the "league of incest" at Villa Diodati.
This calm retelling of the events that led up to the crisis of 1816 plays down the sensation that journalists always want to discuss. Byron's affair with his half-sister, Augusta, is explained as "temperamental conservatism" (akin to Byron's retention of familiar servants); his relationship with Claire is understandable as "he was in an unusually vulnerable state, and Claire was a woman who would prove sexually attractive to many men in the future" (inadmissible evidence, surely?). Whether sympathy to one subject makes a group biography more accurate is debatable.
Ellis rescues Byron from the charge of emotional duplicity but Shelley, we are told, "could often persuade himself that he was acting from the highest principles, whatever he did". Ellis refutes accusations of plagiarism in Manfred by dropping someone else in it: "Byron would never have made a deliberate, unacknowledged borrowing from another writer (as Coleridge does in his 'Hymn before Sunrise')."
The book distils copious research in a convivial and occasionally offhand manner, so Byron and Shelley went to "Oxbridge", Madame de Stael "throws the occasional hysterical fit" and Rousseau's Julie is "a painfully long novel".
Ellis' amassing of biographical subplots creates a richly peopled context: it is oddly satisfying to be made aware that Edward Gibbon almost married the woman who later became Madame de Stael's mother.
The history of things that didn't happen holds peculiar relevance for a study that turns 1816 into a non-event, a few months of baffled attempts to lose his identity that would teach Byron "that he was not a Romantic poet after all".
Ellis has comparatively little to say about Byron's poetry, and he obviously thinks that the Shelleys made a better job of Alpine scenery, but his narrative of criss-crossing pathways details with brilliant economy the way in which "that summer" failed to answer the lonely searches of all those involved.
On his last excursion in Switzerland, Byron and his companion wrote their names on a bit of paper, which they placed under a stone near a blue flower. "This was a strange gesture," Ellis muses, leaving us to recall Rousseau's ecstasy over blue flowers in The Confessions - "Voilà la Pervenche!" (which Byron quotes elsewhere): such intensity over something so small, Rousseau says, allows the reader to judge how deeply he felt about a formative stage of his life.
Ellis keeps the history of Byron's time in Geneva as low-key and matter-of-fact as possible, but terrible emotional wreckage (and not just Byron's) is always only just off-stage.
Byron in Geneva: That Summer of 1816
By David Ellis. Liverpool University Press. 224pp, £25.00. ISBN 9781846316432. Published 16 May 2011