In
1909,
Commander, later
Captain,
Sir Mansfield Cumming became the first head of the Foreign Section of the British
Secret Service Bureau, responsible for gathering
intelligence overseas.
By
1922 Cumming's section had become a separate Service with the title
SIS, commonly known as
MI6. Cumming signed himself 'C'. The tradition of the Service is that all Chiefs are known as ‘C’ and sign their documents using green ink.