The Polish Cipher Bureau deserves the credit from breaking the Enigma codes.
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In December 1932, the Polish Cipher Bureau first broke Germany's War II, on 25 July 1939, in Warsaw, they presented their Enigma-
from wiki Enigma Machine
decryption techniques and equipment to French and British
military intelligence.[3][4] Thanks to this,[5] during the war, Allied
codebreakers were able to decrypt a vast number of
messages that had been enciphered using the Enigma.
The intelligence gleaned from this source, codenamed "Ultra"
by the British, was a substantial aid to the Allied war effort.[6]