The e olu ion o he B i ish sec e se ice
and he ole o Alas ai Gu h ie Dennis on
Michal Bokša
Being my a he ’s son seemed o be such an oppo uni y. I knew enough o his
c yp og aphic wo k du ing and be ween he wo wo ld wa s o guess he e would
be aluable and impo an books o be w i en abou he ac i i ies o he Go e n-
men Code and Cyphe School… Howe e , while he was s ill ali e I knew he would
o bid i . So I old a iend a Secke & Wa bu g — Da id Hol — a li le abou
Ble chley Pa k. He made a ew enqui ies and wi hin days GCHQ ( he successo
o GC&CS) had descended on my a he ’s e i emen co age asking him how he,
he mos disc ee o all ci il se an s, could ha e become a secu i y isk in his old
age. Rema ks we e made abou wi hholding his pension. He was u ious, I was
apologe ic.1
F om Robin Dennis on’s quo e, ela ed o ac i i ies o his a he Alas ai Gu h ie Den-
nis on (AGD) wi hin Go e nmen Code and Cyphe School (GC&CS),2 i is appa en
ha de e mining somebody’s ue ole in any sec e in elligence se ice migh no al-
ways be a ully a ainable ask as GC&CS, gi en i s peculia na u e, will ne e yield all
o i sec e s.3 Howe e , con on ing a la ge numbe o di e en sou ces should p o-
ide an o e all be e pic u e o bo h GC&CS and Alas ai Dennis on’s ole wi hin i .
The i s pa his pape will gene ally ollow a pe iod om 1919 o 1930, hus, elab-
o a ing on he es ablishmen o GC&CS, obs acles Alas ai Dennis on had o ace and
successes he achie ed in his pe iod, especially in he ield o in e nal co-ope a ion
and e ec i eness. The second pa will mos ly ocus on he pe iod be ween 1930 and
1942. I will deal wi h an expansion o GC&CS, beginning wi h a p e-wa ec ui men
p ocess and managemen di icul ies linked o i . The las pa will hen elabo a e
1 DENNISTON, R., Th ee Kind o He o: Publishing he Memoi s o Sec e In elligence People, in:
In elligence and Na ional Secu i y, Vol. 7, 1992, No. 2, p. 112.
2 Uni ed Kingdom’s in elligence and secu i y o ganiza ion es ablished in 1919 in o de o
p o ide signals in elligence un il 1946 when i was ans o med in o he Go e nmen
Communica ion Headqua e s (GCHQ).
3 GREY, C. — STURDY, A., The 1942 Reo ganiza ion o he Go e nmen Code and Cyphe School,
in: C yp ologia, Vol. 32, 2008, No. 4, p. 322.
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MiChAL BOkšA 43
on GC&CS eo ganiza ion in 1942 and on Dennis on’s ole in es ablishing ela ions
be ween US and UK in elligence se ices. The pape will conclude by highligh ing
a complex, ye mos ly posi i e, ole ha AGD played in he de elopmen o GC&CS.
A e he Fi s Wo ld Wa , du ing which B i ish c yp og aphy was p ac ised
in wo sec ions — 40 OB (Room 40)4 and MI 1B,5 he Di ec o o Na al In elligence
(DNI), Admi al Hugh Sinclai , was gi en he ask o o ming one pe manen sec ion
mos ly based on he emnan s o bo h 40 OB and MI 1B. Consequen ly, on 1 No em-
be 1919 GC&CS was es ablished wi h wo main unc ions: a public one and a sec e
one. The public unc ion was “ o ad ise on he secu i y o codes and cyphe s used by
all Go e nmen depa men s and o assis in hei p o ision”, and, a he same ime,
based on a sec e di ec i e, GC&CS was supposed “ o s udy he me hods o cyphe
communica ion used by o eign powe s”.6
Alas ai Dennis on, in 1919, was selec ed, mos ly due o his p e ious wa ime
expe ience om Room 40, o lead he coun y’s peace ime c yp analy ical e o in
he o m o GC&CS.7 As a candida e o his pos he was s ongly p omo ed by Win-
s on Chu chill who in ac made Dennis on’s cha ge o e GC&CS an ul ima um. In one
o his le e s Chu chill w o e “We8 should only consen o pool ou s a wi h he Wa
O ice on condi ion ha Commande A. G. Dennis on is placed in cha ge o he new
depa men … Dennis on is no only he bes man we ha e had, bu he is he only one
we ha e le wi h special genius o his wo k… I he Wa O ice people a e no will-
ing o accep his condi ion, we should p e e o e ain ou s a in he Admi al y.”9
The e o e, he e can be no doub ha in 1919 AGD was pe cei ed as a compe en and
eliable man, sui able o leading he newly o med GC&CS.
F om he e y ou se , howe e , Dennis on’s e o o u he de elop B i ish c yp -
analy ical capabili ies was signi ican ly hampe ed by he Cabine ’s decision o use
some o he dec yp ed messages publicly as poli ical ools. Mainly So ie dec yp s
o e ed B i ain an insigh in o So ie o eign policy, mo eo e , hey p o ided e i-
dence o So ie inancial suppo o le is ex emis s in England and o a emp s o
sub e India. Consequen ly, in Augus 1920, B i ish P ime Minis e Lloyd Geo ge al-
lowed some o he dec yp s o be published in he p ess, hoping o emba ass So ie
go e nmen in o mo e accep able beha iou . As a esul , by Decembe 1920 all So ie
adio a ic disappea ed un il Ma ch 1921 when So ie ansmi e s esumed hei
ope a ions in a mo e secu e cyphe . Dennis on was appalled by he go e nmen ’s de-
4 Sec ion in he B i ish Admi al y o med in 1914 wi h p ima ily ocus on Ge man na al in-
e cep ion and c yp analysis, also known o i s dec yp ion o Zimme mann eleg am.
5 Subsec ion o B i ish Mili a y in elligence ocused p ima ily on Ge man mili a y in e -
cep ion and c yp analysis.
6 DENNISTON, A., The Go e nmen Code and Cyphe School be ween he Wa s, in: In elligence
and Na ional Secu i y, Vol. 1, 1986, No. 1, p. 49.
7 HINSLEY, H., Dennis on, Alexande Gu h ie [Alas ai ], a ailable in: h p://www.ox o ddnb.
com/ iew/p in able/32783).
8 Admi ali y.
9 DENNISTON, R., Thi y Sec e Yea s, A.G, Dennis on’s wo k in signal in elligence 1914–1944,
T owb idge 2007, p. 48–49.
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44 DVACÁTÉ STOLETÍ 2/2016
cision o publish inc imina ing dec yp s, al hough GC&CS b oke new So ie codes
wi hin a ma e o weeks. New dec yp s we e hen o wa ded o he cabine wi h
a cau iona y no e: “i in elligence is used o publici y i will be los o us.” Ne e he-
less, by 1923 he B i ish go e nmen again in en ionally comp omised he dec yp s in
a no e o p o es o he So ie o eign minis e , hus, once again, also comp omising
he wo k o GC&CS.10 As a esul , he Russians s a ed o use new ype o cyphe 11
which ook GC&CS se e al mon hs be o e i succeeded in diagnosing i .12 Finally,
in 1927, he B i ish go e nmen , pa ly o co e i s emba assmen o e he A cos
Raid13 inciden , used a selec ion o So ie in e cep s in o de o jus i y i s decision
o b eak o diploma ic ela ions wi h Moscow. Consequen ly, he So ie Union de-
cided o adop he heo e ically unb eakable “one- ime pad”14 o i s diploma ic a -
ic. Ch is ophe And ew unde lines ha in ega d o he 1927 inciden , Dennis on
w o e bi e ly ha Baldwin’s go e nmen had deemed i “necessa y o comp omise
ou wo k beyond ques ion”. Fu he mo e, And ew a gues ha , as a esul o his,
B i ish c yp analys s we e unable o success ully dec yp ha dly any high-g ade dip-
loma ic a ic o he nex wen y yea s, al hough GC&CS con inued o ha e some
success wi h he communica ion o he Communis In e na ional.15 The publica ion
o So ie dec yp s in 1920, 1923 and 1927 ul ima ely p o ed o be coun e -p oduc i e
and, mo eo e , hey led Dennis on o o e -emphasize he p ese a ion o he sec ecy
o GC&CS’s exis ence.16 As a esul , al eady in 1923 when he Se ices17 wan ed GC&CS
o app oach uni e si y ma hema icians in o de o o m a cad e o c yp analys s o
10 WEST, N., The Sigin Sec e s: The Signal In elligence Wa , 1900 o Today, New Yo k
1988, p. 101–104. Found in PETERSON, M., Be o e Bou bon: Ame ican and B i ish COMINT
E o s agains Russia and he So ie Union be o e 1945, pp. 10–11, a ailable in: h ps://www.
nsa.go /public_in o/_ iles/c yp ologic_qua e ly/be o e_bou bon.pd .
11 ‘Long addi i es’ we e in oduced. Fo mo e on long addi i es see J.H.Til man, Expe ience
1920–1929.
12 TILTMAN, J., Expe iences 1920–1939, (a ailable in: h ps://www.nsa.go /public_in o/_ iles/
ech_jou nals/expe iences.pd ), s. 6.
13 Was a aid (12 May 1927) on he o ices o a B i ish- egis e ed So ie ading company, A -
cos L d., on suspicion ha he company was a on o Communis sub e sion. Howe e ,
no e idence o sub e sion was ound. Found in PALMOWSKI, J., A Dic iona y o Con em-
po a y Wo ld His o y, a ailable in: h p://www.ox o d e e ence.com/ iew/10.1093/oi/au-
ho i y.20110803095422443.
14 One- ime pad comp ises pages o andom numbe s, copies o which we e used by
he sende and ecei e o a message o add and emo e ex a laye s o enciphe men .
One- ime pads used p ope ly only once a e unb eakable. Found in BENSON, R., The Ve-
nona S o y, a ailable in: h ps://www.nsa.go /abou /_ iles/c yp ologic_he i age/publica-
ions/coldwa / enona_s o y.pd
15 ANDREW, C., Ble chley Pa k in P e-Wa Pe spec i e, in: ERSKINE, R. — SMITH, M. (eds.),
Ac ion his day, Cha ham 2001, p. 4
16 FERRIS, J., Whi ehall’s Black Chambe : B i ish C yp ology and The Go e nmen Code and Cyphe
School, 1919–1929, in: In elligence and Na ional Secu i y, Vol. 2, 1987, No. 1, p. 60.
17 Admi al y, he A my, and he Royal Ai Fo ce. Found in WEST, N., His o ical Dic iona y o
B i ish In elligence, Lanham 2005, p. 109.
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MiChAL BOkšA 45
wa ime expansion, GC&CS ejec ed i on he g ounds ha i would make o ganiza-
ion oo publicly known.18 Such an e oneous app oach owa d ma hema icians was,
howe e , la e ec i ied by Dennis on in 1938.19
Fu he de elopmen o B i ish c yp analy ical capabili ies was, howe e , also sig-
ni ican ly hampe ed by he lack o unding ha GC&CS was ecei ing. In ac , GC&CS
was no me ely in luenced by he Geddes axe,20 bu acco ding o Dennis on’s own
wo ds “beyond accommoda ion and sala y GC&CS had no inancial s a us; i became
in ac an adop ed child o he Fo eign O ice21 wi h no amily igh s, and he poo
ela ion o he SIS,22 whose peace ime ac i i ies le li le cash o spa e”.23 Fe is a -
gues ha despi e Dennis on ably de ended and p omo ed GC&CS’s in e es s he was
ea ed only as echnical expe wi h jus a small oice in ac ual policy. Consequen ly,
he o e all unwillingness o alloca e and p o ide mo e inancial esou ces o GC&CS
had signi ican cumula i e e ec s on B i ish c yp ology.24 Fo ins ance, be ween 1929
and 1930 B i ain decided no o de elop a cyphe machine as he T easu y hal ed all
esea ch in o de eloping such de ices.25 In any case, i should be no ed ha Dennis-
on himsel exp essed a g ea in e es in de eloping such a machine and e en ied
o u he explo e i s po en ial and possibili ies o GC&CS. Fo example, John Til -
man, a close iend o AGD and a c yp og aphe a GC&CS, was asked by Dennis on
be ween he yea s 1931 and 1932 o isi he B i ish Tabula ing Machine y Company
o in es iga e he wo k hey we e conduc ing on machines in case hey migh ha e
a c yp ologic applica ion, pa icula ly in he ield o so ing la ge olumes o da a.26
In spi e o he Cabine ’s endencies o use se e al dec yp ed messages publicly
as poli ical ools and despi e he inancial cons ain s imposed upon i , GC&CS was,
be ween he yea s 1919 and 1930, as able as, and possibly supe io o, any o he c yp o-
18 AIR 2/246. S. 22679. Repo o he In e -Se ice Di ec o a e Commi ee, 9 Ap il 1923. Un-
da ed memo andum by he GCCS, ci ca July 1923, passim, in: FERRIS, J., Whi ehall’s Black
Chambe : B i ish C yp ology and The Go e nmen Code and Cyphe School, 1919–1929, in: In el-
ligence and Na ional Secu i y, Vol. 2, 1987, No. 1, p. 60–61.
19 ANDREW, C., op. ci ., p. 8.
20 Commi ee chai ed by Si E ic Geddes ocused on educ ion o public expendi u e. Found
in MCDONALD, A., The Geddes Commi ee and he Fo mula ion o Public Expendi u e Policy,
1921–1922, in: The His o ical Jou nal, Vol. 32, 1989, No. 3, p. 643.
21 In 1922 i was decided o ans e GC&CS om he Admi al y o he Chie Cle k’s Depa -
men o he Fo eign O ice. Found in DENNISTON, The Go e nmen Code…, p. 49–50.
22 Sec e In elligence Se ice, c ea ed in 1909 as he Fo eign Sec ion o he Sec e Se ice
Bu eau. Known since 1916 as MI6, he o ganiza ion’s mili a y in elligence designa ion.
Found in WEST, His o ical Dic iona y…, p. 474.
23 DENNISTON, The Go e nmen Code…, p. 50.
24 FERRIS, op. ci ., pp. 58–59.
25 WO 32/3057. Minu e by S.D.6., 2 Oc . 1929, in: FERRIS, J., Whi ehall’s Black Chambe : B i ish
C yp ology and The Go e nmen Code and Cyphe School, 1919–1929, in: In elligence and Na-
ional Secu i y, Vol. 2, 1987, No. 1, p. 69.
26 NSA. B igadie John Til man A Gian among C yp analys s, a ailable in: h ps://www.nsa.go /
abou /_ iles/c yp ologic_he i age/publica ions/misc/ il man.pd , 14.
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46 DVACÁTÉ STOLETÍ 2/2016
logical o ganiza ion in he wo ld.27 This was indeed achie ed mos ly because o Den-
nis on. Mo eo e , du ing his pe iod AGD managed o u n GC&CS in o an e ec i e
o ganiza ion because he managed o e adica e wi hin i s s uc u es wha he ega ded
o be ‘o icial jealousy’ which had, om his poin o iew, p e en ed any collabo a ion
be ween na al (40 OB) and mili a y (MI 1B) c yp analys s om Oc obe 1914 o Sp ing
1917. In ac , acco ding o Ch is ophe And ew, wi hin a ew yea s o i s ounda ion
GC&CS achie ed success ul coo dina ion o diploma ic and se ice c yp analysis un-
de o e all Fo eign O ice con ol. He con inues by a guing ha such co-o dina ion,
equaled by no o he majo Sigin 28 agency ab oad, was one o he main sec e s o
Ble chley Pa k’s29 success. The success o Dennis on’s GC&CS was, a his ime, u he
con i med by Chu chill’s pe sonal desc ip ion o Sigin , in 1924, as mo e impo an
in he making o o eign and de ense policy han “any o he sou ce o knowledge a
he disposal o he s a e”.30
Soon a e GC&CS was es ablished and as he o ganiza ion was becoming mo e
p o icien in b eaking o eign codes and cyphe s he need o new s a , c yp analys s
and o e all expansion eme ged. In 1923 GC&CS s a ed ha o enla ge i sel g ea ly and
apidly would p o e o be u ile a ha ime.31 Consequen ly, he g ow h o pe sonnel
in he pe iod be ween 1919 and 1935 occu ed in a e y slow and modes ashion. In 1919
GC&CS employed 28 cle ical and 25 c yp ological s a and la e managed o main ain
abou 80 o 90 pe sonnel, including 30 c yp ologis s du ing he 1919–35 pe iod.32 I was
no un il he au umn o 1935 ha he T easu y, a e Dennis on’s endless pleas o an
inc ease in s a o ma ch ising mili a y ac i i y,33 pe mi ed o ec ui an addi ional
hi een cle ks, albei only on a empo a y basis o six mon hs a a ime. Du ing 1937,
he T easu y ag eed o an inc ease in pe manen s a , again mos ly because o Dennis-
on’s ema ks ha GC&CS’s pe sonnel was only able o cope wi h he g owing wo kload
by wo king o e ime.34 Un o una ely, in he ligh o a apid inc ease in he olume o
Ge man wi eless ansmissions, pa icula ly in Enigma35 bu also in he lowe g ade
codes, GC&CS was s ill in despe a e need o mo e pe sonnel.36 Howe e , i was no
me ely a ques ion o budge and numbe s anymo e. GC&CS was also ailing o ise o
27 FERRIS, op. ci ., p. 80.
28 Signals In elligence — ga he ing o in elligence based on in e cep ion o signals.
29 A coun y house in Buckinghamshi e and home o GC&CS since 1939. Found in GCHQ,
WWII: Ble chley Pa k, a ailable in: h p://www.gchq.go .uk/his o y/pages/wwii-ble chley-
pa k.aspx.
30 ANDREW, op. ci ., pp. 10–12.
31 AIR 2/246. S. 22679., Repo o he In e -Se ice Di ec o a e Commi ee.
32 FERRIS, op. ci ., p. 61.
33 Unce ain si ua ion in Spain and E hiopian (Abyssinia) c isis a e explici ly men ioned.
34 HODGES, A., Alan Tu ing: The Enigma, London 1992, p. 147.
35 C yp og aphic machine used by Ge many which was belie ed o be unb eakable. I based
i s cyphe capabili ies on se ies o wi ed o o wheels and plugboa d. Found in WILCOX,
J., Sol ing he Enigma: His o y o he C yp analy ic Bombe, a ailable in: h ps://www.nsa.go /
abou /_ iles/c yp ologic_he i age/publica ions/wwii/sol ing_enigma.pd .
36 HINSLEY, H., B i ish In elligence in he Second Wo ld Wa , I s in luence on S a egy and Ope -
a ions, London 1979, pp. 54–55.
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MiChAL BOkšA 47
he mechanical challenges imposed by hei o eign coun e pa s, he Ge mans in pa -
icula .37 Consequen ly, Hugh Sinclai ,38 “con inced o he ine i abili y o wa ” du ing
1937 ini ia ed he i s majo expansion plans o he GC&CS. In ac , he ins uc ed Den-
nis on, being he ope a ional head o GC&CS, o iden i y “ he igh ype o ec ui ” ha
could po en ially ein o ce GC&CS “immedia ely on he ou b eak o wa ”.39 Dennis on,
ollowing he example o his Wo ld Wa I chie s, decided ha Camb idge and Ox o d
Uni e si ies would ep esen his i s sou ce o ec ui s.40 Consequen ly, a la ge ne -
wo k o con ac s o po en ial candida es was mobilized in a ec ui men p ocess ha
was cha ac e ized as being e y in o mal and pe sonalized.41 Smi h a gues ha p e i-
ously Dennis on had i ually no esou ces wi h which o imp o e GC&CS si ua ion,
bu , wi h Sinclai ’s backing since 1937, he ou ed uni e si ies looking o ma hema i-
cians and linguis s o wo k on Enigma cyphe s, and as a esul he si ua ion began o
change o he be e . This, he a gues, showed a mo e p escience han ei he o his
men had been c edi ed wi h.42 By b eaking wi h misguided p eceden — no ec ui -
ing ma hema icians o c yp analy ical pu poses, which was o iginally es ablished
in he Fi s Wo ld Wa — Dennis on succeeded in b inging in o GC&CS such b illian
ma hema icians as Alan Tu ing and Go don Welchman, bo h o whom made a sig-
ni ican con ibu ion o b eaking Enigma. Ve y soon he i s ma hema icians made
hemsel es indispensable o GC&CS and, as a esul , he ec ui ing p ocess was apidly
ex ended o people om his ield.43 In Augus 1939, only a ew weeks be o e wa was
decla ed, GC&CS mo ed o i s new home in Ble chley Pa k, mainly o secu i y easons
bu , also, because o i s con enien loca ion, hal way be ween Ox o d and Camb idge,
and he u u e need o mo e space.44
The beginning o he Second Wo ld Wa and he sudden apid g ow h o bo h
GC&CS’s pe sonnel and i s needs c ea ed new managemen demands and challenges
o which, howe e , Dennis on s uggled o espond app op ia ely. GC&CS expanded
wi h exponen ial apidi y o e he i s eigh een mon hs o he wa .45 In ac , i had
quad upled in size be ween la e 1939 and ea ly 1941 when i e en eached a s a o 900
pe sonnel.46 Acco ding o Robin Dennis on AGD was no , howe e , a man who ound
leade ship easy and could no play a commanding ole well amongs he bu eauc a s
and poli icians wi h whom he had o deal.47 Un o una ely, i seemed ha , a i s ime
37 HODGES, A., op. ci ., pp. 147–148.
38 By now he chie o Sec e Se ice.
39 JEFFERY, K., MI6 he His o y o he Sec e In elligence Se ice 1909–1949, London 2011, p. 317.
40 WELCHMAN, G., The Hu Six s o y: b eaking he Enigma codes, Cleobu y Mo ime 1997, p. 9.
41 JEFFERY, MI6 he His o y…, p. 317–318.
42 SMITH, M., In oduc ion o: F om Ama eu s o P o essionals: The GCCS and Ins i u ions build-
ing in Sigin , in: ERSKINE, R. — SMITH, M. (eds.), Ac ion his day, Cha ham 2001, p. 386.
43 ANDREW, pp. 8–10.
44 WELCHMAN, G., op. ci ., pp. 9–10.
45 JEFFERY, MI6 he His o y…, p. 745.
46 DAVIES, P., F om Ama eu s o P o essionals: GC&CS and Ins i u ion Building in Sigin , in: ERS-
KINE, R. — SMITH, M. (eds.), Ac ion his day. Cha ham 2001, pp. 395–397.
47 DENNISTON, Thi y Sec e Yea s…, p. 74.
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o apid g ow h, GC&CS needed p ecisely ha — a leade wi h he abili y o ha ness
u he suppo om bu eauc a s and poli icians. Wi hou addi ional esou ces (no
jus people bu also equipmen such as bombs48 and adio se s), GC&CS’s codeb eak-
e s knew hey would no be able o cope. Howe e , since so ew people we e allowed
o know abou he wo k being done a Ble chley Pa k Dennis on’s eques s o mo e
esou ces we e ejec ed.49 Addi ionally, AGD was by no means a delega o and in-
s ead ied o un GC&CS as a one-man ope a ion long a e i should ha e become
a managemen s uc u e, due o i s expanding size.50 This pa icula aspec o Dennis-
on’s leade ship, which p o ed o be so e ec i e when GC&CS was a ela i ely small
ins i u ion, suddenly became a majo obs acle o highe e ec i eness wi h he apid
in lux o new pe sonnel. Consequen ly, in e -GC&CS dispu es and pe cep ible dis-
ag eemen s abou Dennis on’s decision-making s a ed o occu . Ralph Benne ,
c yp og aphe a Ble chley Pa k, ecalled: “Dennis on […] ound himsel in cha ge
o a huge g owing o ganiza ion, a lo o us younge and in some way hinking along
di e en lines, and he go a bi ou da ed…”51 Quo es such as his accu a ely desc ibe
he sen imen s ha we e p esen inside GC&CS in 1941 and ea ly 1942.
The g owing dissa is ac ion wi h Dennis on’s leade ship was, be ween la e 1941
and ea ly 1942, conside ably highligh ed mainly by a so-called “le e o Downing
S ee ” and by he “Hu 352 dispu e”, whe e he cumula i e e ec o hese inciden s
se ed as one o he p e ex s o GC&CS eo ganiza ion in 1942 h ough which Den-
nis on was sidelined and mo ed om Ble chley Pa k o Be kley S ee 53 in Lon-
don.54 As GC&CS eached i s sou ces and adminis a i e c isis in he au umn o
1941, which ansla ed i sel in o an in e nal managemen s uggle, (d i en o some
ex en by i s unmanageable size and by he p og essi e e osion o adi ional in-
s i u ional bounda ies) on 21 Oc obe 1941 ou leading c yp analys s55 decided o
make an appeal (a le e o Downing S ee ) o mo e inancial sou ces di ec ly o
Wins on Chu chill.56 Al hough he le e i sel was a success om GC&CS’s pe -
48 De ice cons uc ed in o de o help o deciphe Enigma’s sec e messages. Found in ERS-
KINE, R., The Poles Re eal hei Sec e s: Alas ai Dennis on’s Accoun o he July 1939 Mee ing a
Py y, in: C yp ologia, Vol. 30, 2006, No. 4, pp. 296–299.
49 SMITH, M., S a ion X: he codeb eake s o Ble chley Pa k, London 1998, pp. 79–80.
50 DENNISTON, Thi y Sec e Yea s…, p. 74.
51 SMITH, S a ion X: he codeb eake s…, p. 93.
52 As Ble chley Pa k apidly expanded, he need o addi ional accommoda ion and space
g ew. Wooden hu s we e he e o e e ec ed p o iding a wo kspace o one o mo e in elli-
gence uni s. Hu 3 housed ai and mili a y in elligence uni s. Found in BRUNT, R., Indexes
a he Go e nmen Code and Cyphe School, Ble chley Pa k, 1940–1945, in: Ame ican Socie y
o In o ma ion Science and Technology, 2004, p. 291.
53 A e 1942 GC&CS’s eo ganiza ion AGD was gi en a cha ge o e he Sigin sec ion p oduc-
ing diploma ic and comme cial in elligence which was mo ed o Be keley S ee . Found
in HOWE, G., Ame ican Signal In elligence in No hwes A ica and Wes e n Eu ope, in: Uni ed
S a es C yp ologic His o y, Vol. 4, 2010, No. 1, p. 158.
54 GREY, C. — STURDY, A., op. ci ., p. 324.
55 Namely: Alan Tu ing, Go don Welchman, Conel Alexande , S ua Milne -Ba y.
56 DAVIES, F om Ama eu s o P o essionals…, p. 397.
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MiChAL BOkšA 49
spec i e as Chu chill immedia ely esponded wi h his amous “Make su e hey
ha e all hey wan …”, o Dennis on, ha ing been bypassed by his subo dina es, i
was a he an emba assmen which had de imen al e ec s on his epu a ion.57
This sugges ed, o some ex en , AGD’s ela i e ine ec i eness and incapabili y o
secu e he essen ial unding ha GC&CS needed by himsel . Howe e , i should
be no ed ha , in 1941, Dennis on had been se iously ill and was o en absen be-
cause o his. Ne e heless, he le e o Downing S ee was s ill an indica ion ha
AGD had p obably los con idence o some o his colleagues.58 The second c ucial
e en , which unde mined AGD’s leade ship, was linked o he dispu e in Hu 3 ha
was ongoing du ing he la e pa o 1941 and ea ly 1942 as he heads o he Hu 3
mili a y and he ai ad ise s a emp ed o expand hei ole o include con ol o
all epo ing. The a mosphe e became so in ense o he poin ha s anda d ou pu
was becoming a ec ed. As a esul , S ewa Menzies59 had o in e ene on se e al
occasions. F om such an expe ience he in e ed ha Dennis on was no longe ca-
pable o con olling such a apidly g owing o ganiza ion as GC&CS.60 Thi dly, and,
pe haps, no such a equen ly men ioned eason as o why AGD’s posi ion wi hin
GC&CS became so s ongly weakened, was linked o he Feb ua y 1941 disco e y
ha wo key adminis a i e posi ions, he chie o bille ing o ice and he ‘aun ie’
o young emale sec e a ies, c yp og aphe s and se ice people we e bo h assigned
o Dennis on’s pe sonal iends. Robin Dennis on unde lined ha i was ine i a-
bly assumed ha AGD was ou o his dep h, despi e, as he also a gues, hose wo
appoin men s ac ually ha ing u ned ou well.61 Ne e heless, adminis a ion and
managemen e o m was a his poin only a ma e o ime.
The eo ganiza ion in 1942 has been gene ally desc ibed as a ans o ma ion om
Dennis on’s ‘laissez- ai e’ sys em in o Edwa d T a is’s62 con ol egime. Howe e , his
p o ed o be only pa ly ue.63 I is wi hou ques ion ha T a is and he 1942 eo ga-
niza ion igge ed an adminis a i e e olu ion which a leas ins alled he manage-
men o in elligence in o line wi h i s mode o p oduc ion.64 T a is also success ully
unde ook s eps o esol e he qua els in Hu 3 by appoin ing E ic Jones65 as i s new
Head, bu i should no be hough ha all endemic p oblems o Ble chley Pa k sud-
57 SMITH, S a ion X: he codeb eake s…, pp. 80–81.
58 GREY, C. — STURDY, A., op. ci ., pp. 322–323.
59 The head o MI6 since 1939 and, as such, was also he Di ec o o GC&CS (supe io o
AGD). Found ERSKINE, R. — MICHAEL, S., Ac ion his day. Cha ham 2001, p. x .
60 SMITH, S a ion X: he codeb eake s…, pp. 92–93.
61 DENNISTON, Thi y Sec e Yea s…, p. 15.
62 T a is was a depu y o AGD un il Feb ua y 1942, when he became Depu y Di ec o in
cha ge o he se ices‘ side o GC&CS. He la e became he Di ec o o GC&CS in Ma ch
1944. Found in ERSKINE, R., MICHAEL, S., Ac ion his day, p. x .
63 GREY, C. — STRUDY, A., op. ci . p. 325.
64 HODGES, A., op. ci ., p. 223.
65 E ic Jones was an ai in elligence o ice who augmen ed he Hu 3 sys em wi h a eam o
du y o ice s who swi ched he lead o each shi . Found in SMITH, S a ion X: he code-
b eake s…, p. 93.
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50 DVACÁTÉ STOLETÍ 2/2016
denly disappea ed, al hough he o e all si ua ion imp o ed signi ican ly.66 I should
be no ed, howe e , ha T a is, in his annual epo o 1942, acknowledged all he ad-
minis a i e di icul ies bu also w o e “… i mus be ecognized ha he new Admin-
is a ion has had he ad an age ha many o he plans laid unde he old egime [i.e.
Dennis on’s enu e] ha e come o ui ion du ing he pas yea .” Consequen ly, i is un-
jus i ied o simply s a e ha Dennis on’s sys em was no hing o he han ‘laissez- ai e’.67
Ne e heless, Dennis on’s eloca ion o Be kley S ee , as men ioned abo e, can be
easily in e p e ed as a de ac o demo ion a e decades o signi ican wo k and e o .68
AGD’s las majo con ibu ion o he wo k o GC&CS, which o igina ed la gely
om his own ini ia i e, was his abili y o lay down he basis o u u e US-UK Si-
gin coope a ion.69 Since ea ly 1941 Dennis on had been ins umen al in p omo ing
ull coope a ion be ween GC&CS and bo h he Uni ed S a es’ a my and na y code-
b eaking uni s.70 A he same ime AGD ied, du ing his wo No h Ame ican is-
i s, o in ol e he Canadian side wi hin his coope a ion in o de o es ablish USA-
Canada h ee-way liaison wi h Ble chley Pa k.71 I should be no ed ha such e o s
we e no ouble- ee, especially since GC&CS had conce ns abou he ex en o
which in o ma ion should be sha ed wi h he Ame ican side as i s secu i y p ac ices
we e ega ded as inadequa e and could allow he Ge mans o iden i y and co ec
hei own c yp ologic ulne abili ies.72 Consequen ly, o example, when he Sinko
mission73 a i ed a Ble chley Pa k in Feb ua y 1941, i belie ed, mos ly because o
B i ish sec ecy and hesi ancy, ha key in o ma ion was in ac wi hheld om i . Al-
hough, ollowing Chu chill’s app o al, he p incipal sec e ela ed o bombes, ma-
chines used o b eak Enigma, was e ealed.74 Such an a mosphe e o unce ain y,
despi e ep esen ing a no able obs acle o UK-US Sigin coope a ion, was b idged o
a la ge ex en by Dennis on himsel whose e o and pe sonal ela ions wi h leading
Ame ican c yp ologis s (especially William F iedman, bu also Ab aham Sinko and
F ank Rowle ) p o ed o be ins umen al as exp essed in hei le e s and co espon-
dence.75 Mo eo e , AGD’s suppo o u he US-UK Sigin exchange could also be
demons a ed by he ac ha , o ins ance, when Til man was p epa ing o a ou
week isi o Ame ican signals in elligence acili ies in Ma ch 1942, he was ins uc ed
by Dennis on o e ec a comple e in e change o all echnical knowledge and o p o-
66 GREY, C. — STURDY, A., op. ci ., p. 325.
67 (NA/HW 14/67). Found in GREY, C. — STRUDY, A., op. ci ., p. 324.
68 GREY, C. — STURDY, A., op. ci ., p. 322.
69 WELCHMAN, G., op. ci ., p. 10.
70 HINSLEY, H., Dennis on, Alexande …
71 DENNISTON, R., Thi y Sec e Yea s…, p. 15.
72 NSA. B igadie John Til man…, pp. 32–33.
73 Sinko mission was a join US A my and Na y eam ha deli e ed o GC&CS clone o
he Japanese diploma ic se ice’s ciphe machine along wi h o he codeb eaking ma e i-
al. Found in ERSKINE, R., Wha did he Sinko mission ecei e om Ble chley Pa k?, in: C yp-
ologia, Vol. 24, 2000, No. 2, pp. 97–98.
74 ERSKINE, Wha did he Sinko …, pp. 97–98.
75 DENNISTON, R., Thi y Sec e Yea s…, p. 44, 82.
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