Book excerpt: Throughout Britain's history, one factor above all others has determined the fate of the nation: its navy. N. A. M. Rodger's definitive account reveals how the political and social progress of Britain has been inextricably intertwined with the strength - and weakness - of its sea power, from the desperate early campaigns against the Vikings to the defeat of the great Spanish Armada. Covering policy, strategy, ships, recruitment and weapons, this is a superb tapestry of nearly 1,000 years of maritime history. 'No other historian has examined the subject in anything like the detail found here. The result is an outstanding example of narrative history' Barry Unsworth, Sunday Telegraph