When is an acceptable book marginal? When there are already better books available. This Succinct survey of Viking customs, conquests and settlements covers a considerable area with pleasing directness, but neither the style nor the physical presentation is distinguished. Both the American Heritage volume, The Vikings (1964) and Boucher, Sea Kings and Dragon Ships (1964) incorporate details of recent discoveries, both are better written, and the former is outstanding for pictorial documentation. Add the Sellman, Burland and Rich books, and the, contribution of this one is negligible.