Pierre, marquis de Ségur (13 February 1853, Paris – 13 August 1916, Poissy) was a French writer and historian, elected a member of the Académie française in 1907. The eldest son of Anatole, marquis de Ségur, and of Cécile Cuvelier, he was thus the grandson of Sophie Rostopchine, Comtesse de Ségur.