Wilberforce was a cat who lived at 10 Downing Street between 1973 and 18 May 1986 and served under four British Prime Ministers: Edward Heath, Harold Wilson, Jim Callaghan and Margaret Thatcher. His chief function was to catch mice, in which role he was the successor to Peta. In life he had been referred to as "the best mouser in Britain", as befitted his role.
