There has been a resident cat in the British government employed as a mouser and pet since the 16th century, although modern records date only to the 1920s.

[6] Official records, however, released into the public domain on 4 January 2005 as part of the Freedom of Information Act 2000 only date back to 3 June 1929,[7][8] when A.E.

Banham at the Treasury authorised the Office Keeper "to spend 1d[b] a day from petty cash towards the maintenance of an efficient cat".

[11] The cat with the longest known tenure at Downing Street is Peter III, who served for over 16 years under five different prime ministers: Clement Attlee, Winston Churchill, Anthony Eden, Harold Macmillan and Alec Douglas-Home.

[13] In 2004 Robert Ford, a political scientist at the University of Manchester, reported on a YouGov survey on partisan reactions to the Downing Street cats.