Mi5

[Lenka]

Where does the abbreviation "MI5" come from?

[rewboss]

The "MI" stands for "Military Intelligence" -- "Intelligence" here means "spying".

Nobody knows exactly how many MI departments there are. Some of them are secret, some were only ever temporary, some may not be real at all. Schott's Original Miscellany very tentatively lists the following departments:

MI 1: Director of Military Intelligence; also cryptography
MI 2: Responsible for Russia and Scandinavia
MI 3: Responsible for Germany and Eastern Europe
MI 4: Aerial reconnaisance during World War II
MI 5: Domestic intelligence and security
MI 6: Foreign intelligence and security
MI 8: Interception and interpretation of communications
MI 9: Clandestine operations -- escape and evasion
MI 10: Weapons and technical analysis
MI 11: Field security police
MI 14: German specialists
MI 17: Secretariat body for MI departments
MI 19: Prisoner of War debriefing unit

[Lenka]

Originally Posted by rewboss

The "MI" stands for "Military Intelligence" -- "Intelligence" here means "spying".

Nobody knows exactly how many MI departments there are. Some of them are secret, some were only ever temporary, some may not be real at all. Schott's Original Miscellany very tentatively lists the following departments:

MI 1: Director of Military Intelligence; also cryptography
MI 2: Responsible for Russia and Scandinavia
MI 3: Responsible for Germany and Eastern Europe
MI 4: Aerial reconnaisance during World War II
MI 5: Domestic intelligence and security
MI 6: Foreign intelligence and security
MI 8: Interception and interpretation of communications
MI 9: Clandestine operations -- escape and evasion
MI 10: Weapons and technical analysis
MI 11: Field security police
MI 14: German specialists
MI 17: Secretariat body for MI departments
MI 19: Prisoner of War debriefing unit

Thank you very much, rewboss. I just wonder whether you remember this all or whether you've simply copied it from somewhere. I suppose the second case is the right one .

[rewboss]

As I said, I got the list from Schott's Original Miscellany.

[Anglika]

MI5 | Frequently Asked Questions: History for their own explanation.