The Secret Intelligence Service has had numerous names over the years, famously referred to as #MI6.
But what other names have there been? A thread🧵
👀 SIS emerges from the Secret Service Bureau, formed in July 1909. Initially seen as covering domestic and overseas intelligence, the SSB soon splits into Home and Foreign sections. In 1916, the Foreign section takes the name MI1(c).
Yet there seemed to be confusion over the actual name. SIS is adopted in early 1920, but "Special" and "Secret" was used at several points. The "Foreign Office service" - a reflection of the FO's control - appears, and "C's organisation" - a reference to "Chief" - is also used.
Though Secret Intelligence Service, the title today, is formally adopted in early 1920, the cover name MI6 - used by most people today - used at the start of #WW2, is famous. Secret Service, abbreviated to S.S., is also used, though it thankfully disappears.
✍️ The "friends" is another internal reference to SIS. Here there's a reference to "Mr. Hayter's friends", referring to the Permanent Under-Secretary's private secretary, and, from 1949, the head of the Permanent Under-Secretary's Department, who liased with SIS.