Marie D' Agoult

French author, known also by her pen name, Daniel Stern.

She entered into an early marriage of convenience with Charles Louis Constant d'Agoult, Comte d'Agoult on 16 May 1827, thereby becoming the Comtesse d'Agoult. They had two daughters. From 1835 to 1839, she lived with virtuoso pianist and composer Franz Liszt, who was six years younger, and was then a rising concert star. She became close to Liszt's circle of friends, including Frédéric Chopin, who dedicated his 12 Études, Op. 25 to her (his earlier set of 12 Études, Op. 10 had been dedicated to Liszt). D'Agoult had three children with Liszt; however, she and Liszt did not marry, maintaining their independent views and other differences while Liszt was busy composing and touring throughout Europe.

Her daughter was Cosima (1837–1930), who first married pianist and conductor Hans von Bülow and then composer Richard Wagner.

Her best-known work (written as "Daniel Stern") is the Histoire de la révolution de 1848 (appearing from 1850–53, in 3 volumes).

She died 5 March 1876.