A beguiling, sweeping history of civilisation and what it means to be civilised. It 'turns 5,000 years of history outside in.'

Historian David Frye presents a bold new thesis on how 'civilization' happens-the epic story of history's greatest manmade barriers, from ancient times to the medieval era and into the present.

At the dawn of humanity's ascent, there was only bloody conflict: nomadic tribes slashing at each other, and each man bred to a life of struggle and pillage. But then came the invention of the wall, dividing populations into two opposing groups. On one side were those who gained enough of a respite from the clash of arms to think, create, preserve, trade. On the other were the unwalled, warriors driven by the search for plunder.

In Walls, historian David Frye shows us what each side gained-and lost-with their decision about how to live. The stars of each chapter are the walls themselves-rising up in places as ancient and exotic as Mesopotamia, Babylon, Greece, China, Rome, Mongolia, Turkey, Afghanistan, Western Europe, and even Central and North America. As we journey across time and place, we discover thousand-mile-long walls in the desert wastes of Turkistan; learn of bizarre Spartan rituals; watch Genghis Khan drive his miles-long horde across the steppe; witness the epic siege of Constantinople; feel chilled at the extermination of French explorers of the lower Mississippi; inhale the gunpowder-scented air of France's Maginot Line; and visit some of the seventy border walls that have been erected in just the past decade.

With provocative insight, Walls charts the centuries-long uneasy tension between the walled and unwalled, showing that walls profoundly shape the human psyche. Creativity, vigour, hardiness, the urge to make one's mark-all depend heavily on whether one lives inside or outside a barrier. Frye's clarion call: walls make civilization possible, but if we depend on them too heavily, they also create a dangerous vulnerability.

'This is history with all the eerie qualities of a short story by Borges: emperors wait for barbarians, labyrinthine complexes of walls are discovered in mysterious deserts. A haunting and brilliant achievement.' - Tom Holland, author of Rubicon and Persian Fire