Henry Landau OBE (7 March 1892 – 20 May 1968) was a South African World War I volunteer who served with the British Army's Royal Field Artillery when he was recruited into what is now known as the SIS (MI6). He was notable as the handler of one of the most effective spy rings of the First World War, La Dame Blanche, and later wrote a number of bestselling novels about his experiences during the war.