* Posts by GPCC_Decodes

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Bletchley Park spat 'halts work on rare German cipher machine'

GPCC_Decodes

GPCC Decodes

The world owes a debt of gratitude to the staff at Bletchley Park and the groundbreaking Polish cryptanalysts who preceeded them.

The BP GPCC intel decrypts were declassified in 1997 / 98 and are held in the National Archives (PRO) at Kew for all to examine.

The GPCC mesages relate to the daily decodes of Concentration Camp inmate populations, as intercepted & decoded in 1942 / 43.

These primary source intel decrypts, known as German Police Concentration Camp, (GPCC) decodes, were first alluded to by Sir Frank Hinsley in 1981 in the official history, British Intelligence in the Second World War.

Hinsley described these as the "Vital statistics" of the Concentration Camps thus:

“From the spring of 1942 until February 1943, when it ceased to be sent by W/T, GC and CS decrypted in another cypher a daily return of prisoners at Dachau, Buchenwald, Auschwitz and seven other concentration camps – not all of them, but a good cross section.*

The daily return consisted of a series of unheaded, unexplained columns of figures which GC and CS worked out to mean:

(a) number of inmates at the start of the previous day,

(b) new arrivals,

(c) departures by any means, and

(d) number at the end of the previous day.

It also specified the various categories of prisoner, such as Politicals, Jews, Poles, other Europeans and Russians.

GC and CS interpreted column (c) – ‘departures by any means” – as being accounted for primarily by deaths. The returns from Auschwitz, the largest of the camps with 20,000 prisoners, mentioned illness as the main cause of death, but included references to shootings and hangings. There were no references in the decrypts to gassing."