Trần Lệ Xuân, more popularly known in English as Madame Nhu, was the de facto First Lady of South Vietnam from 1955 to 1963. She was the wife of Ngô Đình Nhu, who was the brother and chief advisor to President Ngô Đình Diệm. As Diệm was a lifelong bachelor and because she and her family lived in Independence Palace together with him, she was considered to be the first lady.
Known for her harsh and incendiary comments that denounced anti-government protests by some Buddhist sects and the strong U.S. influence and presence in the country, she had to live in exile in France after her husband and her brother-in-law, Diệm, were assassinated in 1963.