What is Five Eyes intelligence alliance?

Subject :IR

Section: Groupings

The ‘Five Eyes’ is a multilateral intelligence-sharing network shared by over 20 different agencies of five English-speaking countries — Australia, Canada, New Zealand, the United Kingdom and the United States. It is both surveillance-based and signals intelligence (SIGINT). Intelligence documents shared between the member countries are classified ‘Secret—AUS/CAN/NZ/UK/US Eyes Only,’ which gave the group its title ‘Five Eyes.’

Historical background:

The origins of the FVEY can be traced to informal secret meetings during World War II between British and American code-breakers.
The treaty called the British-U.S. Communication Intelligence Agreement, or BRUSA (now known as the UKUSA Agreement), was signed between the State-Army-Navy Communication Intelligence Board (STANCIB) of the U.S. and the London Signal Intelligence Board (SIGINT) of Britain.
Its scope was limited to “communication intelligence matters only” related to “unrestricted” exchange of intelligence products in six areas: collection of traffic; acquisition of communication documents and equipment; traffic analysis; cryptanalysis; decryption and translation; and acquisition of information regarding communication organisations, practices, procedures, and equipment. The arrangement was later extended to ‘second party’ countries —Canada joined in 1948, while Australia and New Zealand became part of the alliance in 1956.
It was started before the US formally entered the war, followed by the Allies’ 1941 Atlantic Charter that established their vision of the post-war world.