Sir Malcolm Delevigne, [link will need Athens], that's him on the left, was the British representative at Geneva in 1924/5, and at many other drug related conferences, he was an expert on the trade - and on health and safety at work. The American representatives would also repay further research: Stephen Porter and Bishop Brent.
Perhaps most interesting is the man who put Indian Hemp on the table, Dr Mohamed Abdel Salam El Guindy, the Egyptian representative. As Kendell puts it: "Without the Egyptian initiative and Dr El Guindy’s single-minded determination, Indian hemp would never have been brought under the controls of the 1925 Convention." There is no doubt that the picture he painted of the effects of Indian Hemp was, as best, over-colourful.
El Guindy was supported by the Turkish and Greek representatives - which suggests a joint interest in a regional economic situation connected with Indian Hemp. This too wants further research.
We must also consider the role of British India, which did not want to ruffle any Indian sensibilities over the use of Bhang. (Sir Malcolm's brother was a member of the Indian Civil Service, Bartrip).
P. W. J. Bartrip, ‘Delevingne, Sir Malcolm (1868–1950)’, Oxford Dictionary of National Biography, Oxford University Press, 2004
Kendell, R. E. (2003) Cannabis condemned: the proscription of Indian hemp. Addiction, 98, 143–151