Her father , Raymond Bonham Carter , was a banker and his maternal grandfather was H. H. Asquith , a former Prime Minister of the United Kingdom . Her father , Raymond Bonham Carter , was a merchant banker , and served as the alternative British director representing the Bank of England at the International Monetary Fund in Washington , D.C. during the 1960s . He came from a famous British political family , being the son of British Liberal politician Sir Maurice Bonham Carter and renowned politician and orator Violet Bonham Carter , whose father was the Prime Minister of the United Kingdom , H. H. Asquith ( serving 1908 â `` 1916 ) .