Humans did not make history – we played host.

According to the accepted narrative of progress, a few great humans have bent the arc of history. But in this revelatory book, Dr Jonathan Kennedy argues that germs have done more to shape humanity at every stage, from the first success of Homo sapiens over the equally intelligent Neanderthals to the fall of Rome and the rise of Islam.

How did an Indonesian volcano help cause the Black Death, setting Europe on the road to capitalism?

How could 168 men extract the largest ransom in history from an opposing army of eighty thousand?

And why did the Industrial Revolution lead to the birth of the modern welfare state?

The latest science reveals that infectious diseases are not just something that happens to us, but a fundamental part of who we are. Indeed, the only reason humans don’t lay eggs is that a virus long ago inserted itself into our DNA, and there are as many bacteria in your body as there are human cells. We have been thinking about the survival of the fittest all wrong: evolution is not simply about human strength and intelligence, but about how we live and thrive in a world dominated by microbes.

Pathogenesis has been translated into 15 languages.

‘This sweeping history is Kennedy’s debut, and a powerfully argued one… Pathogenesis sets out, like Yuval Noah Harari’s Sapiens or Peter Frankopan’s recent The Earth Transformed, to reinterpret the entire history of mankind… A fascinating and pacey run through the history of humanity from an unfamiliar perspective.’ – Book of the Week, Sunday Times

‘This book challenges some of the greatest cliches about colonialism and leaves you wondering why you ever gave them the time of day. A revelation, and also that rarest thing, a science title that is entirely comprehensible and often a pleasure to read.’ – Sathnam Sanghera, bestselling author of Empireland

‘Pathogenesis is superbly written. Kennedy seamlessly weaves together scientific and historical research, and his confident authorial voice is sure to please readers of Yuval Noah Harari or Rutger Bregman.’ – David Robson, The Times

‘Thrilling and eye-opening. From neolithic diseases to Covid-19, Jonathan Kennedy explores the enormous role played by some of the tiniest life on Earth: the power of plagues in shaping world history.’ – Professor Lewis Dartnell, bestselling author of Origins and Being Human

‘From the fall of Rome to the Spanish conquest of the Americas to the industrial revolution, germs have played as much a role in history as guns, generals and “great men”… Jonathan Kennedy restores the microbes of infectious disease to their rightful place in the story of human evolution and the rise and fall of civilisations. Science and history at its best.’ – Dr Mark Honigsbaum, author of The Pandemic Century

‘Gripping . . . [Kennedy] wrangles an astonishing breadth of material into easily accessible, plain prose. . . . Even readers familiar with the material will find [Pathogenesis] fascinating. . . . Kennedy will leave readers galvanized by the time they flip to the last page, having assured us that we could win the narrative back from germs—if we’re able to muster the political will to do so. Pathogenesis puts us in our rightful tiny place in the universe as this great, big—and terrifying, at times—world spins. But, Kennedy reminds us, we are not helpless.’ —Washington Post

‘Kennedy’s book, which aims to show how infectious disease has shaped us from the time of the Neanderthals to the era of Covid-19, is full of amazing facts… Pathogenesis doesn’t only cover thousands of years of history – it seeks radically to alter the way the reader views many of the (often very well-known) events it describes.’ – Rachel Cooke, Observer

‘Professor Kennedy-drawing on the latest research in fields ranging from genetics and anthropology to archaeology and economics-explores eight major outbreaks of infectious disease across the entire history of civilization… It’s not often you pick up a book that promises to alter your entire understanding of the story of humanity.’ – LitHub

‘An absorbing book… Kennedy’s intertwined story of humanity and humongous disease is told lucidly and knowledgeably, with ample historical context. — Telegraph