Warfare, Raiding and Defence in Early Medieval Britain, by Erik Grigg, Marlborough: Robert Hale, 2018, 224 pp., £25; ISBN 978 0 7198 26788.

A sophisticated analysis of defence in early-medieval Britain that focuses on the widespread building of early-modern dykes in order to thwart the raids that were an incessant feature in conflict in this period. Many dykes were built by the Britons against the Anglo-Saxons, but they were also designed to thwart raids between kingdoms. This pattern of dyke-building can also be seen elsewhere, for example in Denmark.

The research benefits from Light Detection and Recognition in which highly-accurate images of the ground are taken using lasers mounted on low-flying aircraft. At the same time, Erik Grigg draws attention to the difficulties of analysing motives, including the symbolic character of earthworks. As Grigg points out, his research rests on a complex process of cataloguing the earthworks.

An important work of great value for military history, archaeology, and Anglo-Saxon studies.