Tajne Wojskowe Zakłady Wydawnicze

Tajne Wojskowe Zakłady Wydawnicze (translated as the Secret Military Printing Works or the Secret Military Publishing House) was the secret printing and publishing house of the Polish Underground State in Warsaw, Nazi-occupied Poland. It was run, from its creation in late 1940 to disbandment in early 1945, by Jerzy Rutkowski of Bureau of Information and Propaganda of the Polish resistance (Armia Krajowa).

TWZW was likely the largest underground publisher in the world.

First underground press of TWZW started operating in Warsaw in autumn 1940. Before that period, underground presses had to rely on small, amateurish printing presses. TWZW revolutionized the underground printing scene in occupied Poland, by building new underground presses, and organizing the entire network. By early 1944 TWZW had twelve underground centers, including eight printing presses, as well as a bookbinding center, an offset printing center, a foreign-language publication center, and a chemigraphy (zincography) center. Most of its operations were located in Warsaw. In summer 1944 several centers of TWZW were discovered by the German occupiers. During the Warsaw Uprising in late summer of 1944, remaining TWZW operations in Warsaw went public as Wojskowe Zakłady Wydawnicze (Military Publishing House). Early on during the uprising personnel of TWZW attacked and took control of several large, official printing presses in Warsaw. The last publication of Warsaw TWZW was the 102nd issue of Biuletyn Informacyjny, printed on the night of 3 to 4 October, a day after the insurgents surrendered. TWZW was officially disbanded in January 1945 along with the entire Armia Krajowa.

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