The British government has kept a cat on the payroll since 1929

On June 3, 1929, a Treasury official named A.E. Banham authorized the Office Keeper at 10 Downing Street "to spend 1d a day from petty cash towards the maintenance of an efficient cat." The job remains to this day. Britain's official resident cat now carries the title Chief Mouser to the Cabinet Office, and the current officeholder, Larry — a Battersea rescue picked out by David Cameron's family in 2011 after TV cameras caught rats running across the front steps of Number 10 — is the first cat to hold it officially.

The cats don't belong to the prime minister, and their terms rarely line up. Peter III served more than 16 years under five prime ministers, from Clement Attlee to Alec Douglas-Home.

In 2004, political scientist Robert Ford reported on a YouGov survey in which participants saw a photo of Humphrey, the mouser appointed under Margaret Thatcher. Half were told he was Thatcher's cat, half that he was Tony Blair's. Conservative voters liked the cat far more when he was Thatcher's; Labour voters liked him far more when he was Blair's.