On August 9, 1866, when she is twenty years old, Marie marries Alfred Jaëll in the Church of La Madeleine in Paris. He was fifteen years older than her, and was originating in Trieste. He was a pianist virtuoso of international fame, pupil of Chopin.

Marie becomes acquainted soon with a friend of her husband, Franz Liszt, who attended the main European musical centers : Rome, Weimar, Vienna and Paris.

So Marie, young but already famous pianist, is brought to meet all the great musicians of her time : Brahms, Rubinstein and many others.

Marie Jaëll will maintain particularly privileged relations with Liszt, who was for her both a master and a friend. The so extraordinary play of Liszt was for her a true revelation which was to be decisive in the orientation of her life and of her thought thereafter.

In the Paris of the end of this century, Marie Jaëll is in company of the most prestigious writers and poets of the time and among them, Mallarmé, A. Gide, P. Valéry, A. Siegfried, M. Pottecher. She meets also the Alsatian famous ones which set there or make there frequent appearances, Schuré and Albert Schweitzer.

Almost all the writers who maintain a correspondence with Marie have a common point : they are interested in music and musicology.