Foreign and Commonwealth Office migrated archives

The Foreign and Commonwealth Office migrated archives are sensitive and incriminating collections of documents from Britain's former colonial governments that were sent back to the UK (hence migrated) on the eve of decolonisation for storage in the FCO archives to avoid their disclosure and subsequent embarrassment to Her Majesty's Government. A great many similar documents were not repatriated, but instead destroyed.

The fact that it has always been British policy to withdraw or destroy certain sensitive records prior to Independence has never been advertised or generally admitted.

Between 1963 and 1994 the migrated archives were stored in Hayes repository; in 1994 they were moved to Hanslope Park, home of Her Majesty's Government Communications Centre, to save on storage costs. In 1967, in 1974, and again in the early 1980s, Kenya asked for them to be released, but the UK refused.

Ben Macintyre of the Times summarised the procedure for declassifying Foreign Office archival material as follows:

Under the Public Records Act, documents are liable for release to the National Archives after 30 years. Up to 60 per cent of material is shredded and burnt at this stage. Less than 1 per cent is kept secret. Under the present rules, the Foreign Office may retain documents relating to intelligence, national security and defence. Some files transferred to the archives remain closed if they are deemed potentially harmful to international relations or contain personal information. Any decision to retain official documents is subject to scrutiny by the Lord Chancellor's Advisory Council on National Records and Archives, a panel chaired by Lord Neuberger of Abbotsbury, the Master of the Rolls.

Once at Hanslope, reviewing documents for release is a job for seventeen part-time "sensitivity reviewers", mostly retired Foreign Office officials; it is rare for a file to be judged sensitive enough to warrant withholding it in entirety. When it came to the migrated archives, however, the question of whether they fell within the scope of the Public Records Act 1958 was never answered definitively, and so they were conveniently left undisturbed in archival stasis.

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