Niven's grandfather William Degacher was killed in the Battle of Isandlwana (1879), during the Zulu War. She was born in Wales, the daughter of army officer William Degacher (1841–1879) by his marriage to Julia Caroline Smith, the daughter of Lieutenant General James Webber Smith. Henrietta was of French and British ancestry. Niven often claimed that he was born in Kirriemuir, in the Scottish county of Angus in 1909, but his birth certificate shows this was not the case. James David Graham Niven was born in London to William Edward Graham Niven (1878–1915) and Henrietta Julia Degacher. He was the second actor to play the role in a film outside the EON Productions franchise. He plays James Bond in the 1967 spoof Casino Royale, based on the novel of the same.

David Niven (1910-1983) was a British actor.