Originally from Bresse Louhanaise, she worked as a teacher and served in the Resistance during the Second World War.

The daughter of teachers in the Louhans region, where she spent her childhood, Marie Rose Treffot graduated from the École normale supérieure de Sèvres, (1937)[1] and obtained the agrégation of mathematics (1940–41).

She taught at Dreux and Chartres (1940–43), while engaging in the Resistance, within the network "Defense de la France".

In 1951, she joined the editorial office of the women's weekly Elle, where she led the "Parents-enfants" section until 1973.

After her return to France, she published several historical works and novels, which won her many prizes, including the prix Maurice Genevoix.