Mr Chicken was, in 1730, the owner of the property that would become 10 Downing Street. (TV: World War Three)
Sir Robert Walpole, the First Lord of the Treasury, later accepted 10 Downing Street as his official residence in the 1730s. Mr Chicken moved to another house in the street. The property was then refurbished and extended.
Following this, Walpole stipulated that the property should be held for the exclusive use of Britain's heads of government after him. (PROSE: The Time Travellers' Almanac)
In 2006, the Ninth Doctor described Mr Chicken as "a nice man" while telling Rose Tyler about the history of the building. (TV: World War Three)