David White's meticulously researched and brilliantly told account of the Battle of the Atlantic is the first to assess this crucial theatre of the Second World War from the viewpoint of all the protagonists: Germany, USSR, USA, Canada and, above all, the UK. Packed with first-hand testimony from seamen and submariners, White shows the real hardships faced. He also shows how the U-boat threat was countered and eventually defeated, ensuring the survival of Great Britain and thus the defeat of Nazi Germany. The Royal Navy's triumph undoubtedly changed the course of history.