Helen Violet Bonham Carter, Baroness Asquith of Yarnbury (15 April 1887 – 19 February 1969) was a British politician and diarist. She was the daughter of H. H. Asquith, Prime Minister from 1908–1916, and later became active in Liberal politics herself, being a leading opponent of appeasement, standing for Parliament and being made a life peer. She was also involved in arts and literature. Her illuminating diaries cover her father's premiership before and during World War I and continue until the 1960s.
She was Winston Churchill's closest female friend, apart from his wife, and also the grandmother of well-known actress Helena Bonham Carter.
She grew up in a heavily political environment, living in Downing Street at the time her father occupied it, and socialised with the key political figures of her day. She did not go to school, but was educated at home by governesses, and later sent to Paris and Dresden to improve her languages. Her mother, Helen Kelsall (née Melland), died of typhoid fever when Violet was four. Her stepmother was Margot Asquith. Her best friend when she was young was Venetia Stanley who had an affair with her father H.H. Asquith. (Neate,B. Conspiracy of Secrets).
As the Liberal Party fell on hard times in the 1920s, she became a tireless defender of her father and his reputation, beginning by campaigning for him at the 1920 Paisley by-election. She was particularly close to Winston Churchill, a leading light in the Liberals during her father's (and Lloyd George's) administration.