Everyone has heard of the Great Wall of China & knows of Hadrian`s Wall & the other barriers lining stretches of Rome`s imperial frontiers. But Peter Spring`s original new study demonstrates that far from being exceptional, the building of walls & other linear defences was commonplace among the peoples & states of pre-modern era. He finds examples virtually all across the globe & analyses their forms & strategic functions. He finds patterns for their distribution, an important recurrent theme being the divide between settled agriculture & nomads. The author argues that it is mistaken to view such undertakings as necessarily purely defensive measures that might be evidence of insecurity or a `maginot line mentality`, as they were in fact often about aggressive assertion of control over a region or strategic routes. This original & thought-provoking study brings new light & insight to a fascinating & neglected aspect of human political & military history. It The clear text is supported by numerous, specially drawn maps & photographs.