AN INCREDIBLE SURVIVAL — A COMBAT-USED SIGNALBUCH DER KRIEGSMARINE USED BY THE 13TH U-BOAT FLOTILLA, REPLETE WITH SIGNIFICANT NOTATIONS ܫIN VARIOUS HANDS, NUMEROUS TEXT CHANGES, AND APPARE🔯NT BULLET HOLES 

Signalbuchs were used widely by the German Kriegsmarine to aid the U-boats in their communications with bases on shore and surface vessels. The books, contained detailed instructions on communication using flags, Morse code, star and flare signals and much more. The contents and codes used in the books changed so rapidly, that the Kriegsmarine did not have time to print new editions, and so instead, updates would be sent out to the various Signalbuch holders in secret, printed on paper slips that were meant to be glued into the books, replacing the outdated text. Signalbuchs were part of the library of ultra top-secret documents guarded closely by the Kriegsmarine, and along with the Enigma machines, these tools gave the Germans a major technical advantage during the war. These tools were so important, that all German military was under strict orders to burn the Signalbuchs and destroy the Engima machines at even the slightest hint of capture. Because of this, incredibly few of𓄧 these books have survi▨ved. 

The 13th U-Boat Flotilla was a U-Boat unit of the German Kriegsmarine that was stationed in Trondheim, Norway during World War II, the largest German naval base in northern Europe. Founded in June, 1943 under the command of Korvkkpt. Rolf Rüggenberg , the flotilla had a full 55 U-Boats assigned to it. Norway was an incredibly important strategic asset for Germany, as it facilitated access to iron ore from Sweden, and to the North Atlantic and Arctic Oceans. Critical information passed through the Trondheim communications bunker, such as weather observations sent from U-boats in the north Atlantic, among other things. The present Signalbuch was most certainly used to communicate with the Bauaufsicht der Kriegsmarine in Trondheim, and its surv🐠ival 🦂to this day in remarkable indeed.