This article in the January 1986 issue of Cryptologia by leading expert  Ralph Erskine reveals how code-breakers were recruited just before WW2 broke out. In the summer of 1939, due to the fact that throughout the 1930s the Government Code & Cypher School (GCCS) had been starved of funds, there were hardly any cryptologists who could rise to the challenge of deciphering the German codes. So when, in early September 1939, war was looming, the Director of the GCCS, Commander Alastair Denniston, was forced to recruit an emergency team of supposedly large brained cryptologists. Denniston wanted 'men of the Professor type' , which in 1939,  social and intellectual snobbery being what it was, meant academics likely to possess degrees in German, mathematics or classics from Oxford or Cambridge.