From coding to codebreaking: the full Lorenz story

The Norwegian Armed Forces Museum presented an extremely rare World War II machine on a long-term loan to the British National Museum of Computing (TNMOC) at a ceremony held on the occasion. The machine is a Lorenz SZ42, Hitler’s “unbreakable” decipher machine, representing cutting edge technology at the time, which will now be on display at the TNMOC.
Deciphering the ultra-secret messages sent by the Lorenz contributed significantly to shortening World War II. The machine, far more complex than Enigma, could be broken by the codebreakers at Bletchley Park thanks to the work of Bill Tutte.
Tutte made deductions of the architecture of the Lorenz without ever having seen one for real. With Colossus having been built in 1944, the time needed by the Allies for codebreaking was drastically reduced – what would take weeks earlier took only a couple of hours with Colossus. Development of Colossus was headed by Tommy Flowers.
According to estimates, 200 Lorenz machines were in use during World War II, but only four are known to have survived the cataclysm. The machine to be put on display at TNMOC bears the serial number of 1137. It was used by the German headquarters in Lillehamer, north of Oslo. Since Norway was under German occupation until the end of World War II, the German forces presumably received the instruction to surrender via this machine at 24 hours on 8 May 1945.