The following books are highly recommended for anyone with an interest in the U-Boat War. The list is based on nothing more scientific than my own personal tastes and are those I found most enjoyable and helpful.
Dönitz's Crews

French L Maclean
Schiffer Publishing, Altglen, PA ., 2009
A superb, high quality and lavishly illustrated book looking at those who crewed the U-Boats. This study is done by lookling at a number of specific U-Boats with superb photos of the men who crewed these boats, their uniforms, awards, award documents etc. Highly recommended.
U-Boats under the Swastika.

Jak Mallmann Showell.
Ian Allan, Surrey, 1973
One of my earliest purchases and still a firm favourite. First printed over 30 years ago, this is still a superb introduction to the subject. The Second Edition which appeared in 1987 was updated with a whole load of new photos.
U-Boat Commanders & Crews

Jak Mallmann Showell
Crowwood Press, Marlborough, 1998
An excellent reference concentrating on the people rather than the boats. Covers areas such as selection, training, education, ranks, life at sea etc.
U-Boats in Camera

Jak Mallmann Showell
Sutton Publishing, Stroud, 1999
Predominantly a photo book with a superb selection of shots from the collection of the U-Boat Archive (Deutsches U-Boot Museum) with detailed explanatory captions.
U-Boats at War

Jak Mallmann Showell
Ian Allan, Surrey, 2000
Another tremendous work, dealing with little known occasions when U-Boat crews had actually made landings on hostile territory. Heavily illustrated with wartime photos as well as photos taken when the author visited some of these locations.
Enigma U-Boats

Jak Mallmann Showell
Ian Allan, Surrey, 2000
In this work, the author deals with the development of Enigma, the work of the codebreakers at Bletchley Park, and the capture of Enigma machines from boarded U-Boats. Richly illustrated.
U-Boat Warfare

Jak Mallmann Showell
Ian Allan, Surrey, 2002
Another lavishly illustrated work in which the author deals with the development of "Wolf Pack" tactics and how the allies developed counter measures. A highly "readable" work.
Hitler's U-Boat Bases

Jak Mallmann Showell
Sutton , Stroud, 2002
In this title, the author turns his attention to the massive U-Boat bunkers built in Germany and in the occupied territories. Heavily illustrated as usual, with many comparison shots showing what remains of these bunkers today.
The U-Boat Century

Jak Mallmann Showell
Chatham Publishing, London, 2006
This work covers the whole history of German submarines from 1906 right up to the lastest models used by the German Navy today. Richly illustrated
Wolfpacks at War

Jak Mallmann Showell
Ian Allan, Surrey, 2002
Concentrating on what life was like for an operational U-Boat crewman, this large format book contains a wealth of photos and illustrations, many in colour.
U-Boat War Patrol

Lawrence Paterson
Greenhill Books, London, 2004
Superb photographic record of a complete war patrol of U-564 under Teddy Suhren, most of the photos being previously unpublished.
First U-Boat Flotilla

Lawrence Paterson
Leo Cooper, Barnsley, 2002
A detailed history of the first U-Boat Flotilla "Weddigen", in "Diary" form from its creation until 1945.
Second U-Boat Flotilla

Lawrence Paterson
Leo Cooper, Barnsley, 2003
A detailed history of the second U-Boat Flotilla "Salzwedel" in similar format to the previous work.
U-Boat Operations of the Second World War (Vol 1 U1 - U510)

Kenneth Wyn
Chatham Publishing, London, 1997
A real treasure trove of information, with brief career details and operational histories including details of the commanders of the first 510 U-Boats.
U-Boat Operations of the Second World War (Vol 2 U511 - UIT25)
Kenneth Wyn
Chatham Publishing, London, 1998
A real treasure trove of information, with brief career details and operational histories including details of the commanders of the first 510 U-Boats.
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