Using historical records and modern marine archaeology, this book seeks answers to some of the riddles of the 1588 Spanish Armada, the greatest fleet ever assembled in early modern Europe, sent by the King of Spain to accompany a planned invasion of England. Everything went wrong--the more maneuverable British fleet, with longer-range cannons, broke its formations and forced the Spanish to sail north around Scotland and Ireland in a desperate effort to reach home. Heavy gales, treacherous seas, and British-inflicted damage sank many Armada ships. Martin spent years organizing skin-diving expeditions to find out why the Spanish had been so ineffectual. Operating in difficult conditions between rocks, reefs and racing tides, divers gained new data, confirming what the Spanish commander himself probably knew, ""as we who have dived among the timbers of his ships also know, that many of his front-line vessels were weak and totally unsuited to naval warfare"" and that his secondary ships ""might look impressive, but were not likely to be of much use in action."" Recovered cannon show that rushed production and poor technology made inferior weapons. All proving that--although only its top officers guessed it--the supposedly invincible Armada was mainly a bluff intended to frighten the English into political concessions. Martin has produced an arresting blend of historical detective story and diving adventure.