This unique WWII history combines the memoirs of a Nazi Admiral with secret British naval reports for a comprehensive view of the U-Boat war. The memoirs of Admiral Karl Dönitz, Ten Years and Twenty Days, are a fascinating first-hand account of the Battle of the Atlantic as seen from the headquarters of the U-boat fleet. Now, noted naval historian Jak P. Mallmann Showell has combined Dönitz's memoirs in a parallel text with the British Admiralty's secret Monthly Anti-Submarine Reports to produce a unique view of the U-boat war as it was perceived at the time by both sides. The British Monthly Anti-Submarine Reports were classified documents issued only to senior officers hunting U-boats. They were supposed to have been returned to the Admiralty and destroyed at the end of the War, but by chance a set survived in the archives of the Royal Navy's Submarine Museum in Gosport. They offer significant and hitherto unavailable insight into the British view of the Battle of the Atlantic as it was being fought. With expert analysis of these firsthand sources from opposing sides of the conflict, Jak P. Mallmann Showell presents what may be the most complete contemporary account of the desperate struggle in the North Atlantic during the Second World War.