‘I was in the Treasury throughout the war and all the money we either lent or borrowed passed through my hands’—so Keynes, speaking in 1923, airily described his wartime duties. He hardly exaggerated, as he was directly concerned with the strategy of financing Britain's war expenditure and that of her allies, and finally took charge of a division of his own responsible for all of Britain's inter-allied financial arrangements.

He kept a mass of minutes, memoranda, first and second drafts, reports and printed papers documenting this period of his life. By itself, however, the material is incomplete and inconclusive. The records of the Treasury and the Cabinet Office, now made available at the Public Record Office, help in large measure to fill in the gaps and reveal a remarkably influential role for a man between the ages of 31 and 36.

When Keynes entered the Treasury it was a comparatively small group, and the war still seemed a small war. At first he had many jobs, but as the war went on Britain's financial involvement mushroomed, and this national burden became his particular care. The following section does not provide an exhaustive account of his work. The papers reproduced have been chosen to show the different kinds of things that he was doing and his manner of doing them. They are interesting for the light that they throw on his development as an economist or on the similarities and differences in his thinking at this stage and in later years.