The Foreign and Commonwealth Office Migrated Archives are a collection of about 20,000 files and other records created by the governments of 37 British colonial dependencies, removed to the UK at independence, and held clandestinely for decades in various repositories in and around London. They came only from territories administered by the Colonial Office, so not from India and other dependencies administered by the India Office and its predecessors, whose records are in the India Office Records at the British Library.
The Foreign and Commonwealth Office (FCO) was finally forced to admit the existence of the 'migrated archives' in 2011 during the course of the 'Mau Mau litigation', a case brought against the British government by veterans of the 1952–1960 struggle for independence in Kenya who claimed compensation for ill-treatment and torture. Foreign Secretary William Hague announced in the House of Commons on 5 May 2011 that he intended "to release every part of every paper of interest subject only to legal exemptions". The collection was transferred to the UK National Archives (TNA), and opened to the public, during 2012 and 2013. It is held at TNA under the reference FCO 141.[1] There are redactions and closed and retained items, but it appears that nothing was destroyed during the process of transfer. Unknown quantities of related material were destroyed by the British authorities in the former dependencies during the decolonisation period. It is not known if anything was destroyed after the removal to the UK. Certainly some was lost during the many moves from one building to another.
Because of the circumstances of the release of these records it was initially believed that the entire content was sensitive and potentially incriminating. In fact, content is highly miscellaneous and sometimes mundane. FCO 141 also includes files created by the FCO, TNA, and their predecessors which are about the 'migrated archives' rather than part of them. Material in FCO 141 covers dates between 1835 and 2012.