This biography offers to rediscover Eugène Ysaÿe (1858-1931), an emblematic personality of Belgian and international musical life from the 1880s and for five decades. Drawing on a large number of sources (manuscripts, letters, press), some of which are unpublished, it retraces the journey of a multifaceted artist at the same time as the personal journey of a man who experiences, loves, suffers and doubt. This star violinist, conductor and concert organizer rubs shoulders with the greatest musicians of his time, such as Bloch, Busoni, Casals, Cortot, Enesco, Grieg, Kreisler, Rachmaninov or Rubinstein. It spreads and stimulates creation in a unique way, defending with conviction the music of Chausson, Debussy, Fauré, Franck, d'Indy, Jongen, Lekeu, Saint-Saëns and many others, in Europe, but also in Russia and the United States. He also established himself as a composer, devoting himself to musical writing from its beginnings and until his last breath, and as an educator, helping a multitude of young violinists to flourish in their career as performers. or teacher. This publication, which is aimed at both specialists and music lovers, is structured chronologically into five chapters with rich iconography and includes two appendices, the first detailing the compositions, the second the students.