From administrative documents, it is apparent that Reyer wrote innumerable youthful essays and stories, and original dance pieces.
Southern France and Provence held its allure, and Reyer returned there to socialize with local people with whom he loved to play dominoes while smoking a pipe.
His aunt, Louise Farrenc, professor of piano at the Conservatoire and a talented composer in her own right, directed Reyer's early musical studies.
The same year, he composed Érostrate, an opera in two acts, which was played in August 1862 in Baden-Baden, under the auspices of great families in Europe, which earned him the distinction of receiving the Red Eagle from the hands of the Queen of Prussia.
The best-known of his five operas is Sigurd (1884); it was quite popular in France during its initial production there (it had its premiere in Brussels at the Théâtre de La Monnaie in January 1884), and is sometimes (although rarely) revived.
Sigurd is based on the Scandinavian legends of the Edda Völsunga saga (Nibelungenlied), the same source which Richard Wagner drew upon for the libretto for his Ring cycle.
Listening to Sigurd, one cannot help but hear echoes of Les Troyens or Benvenuto Cellini, imbued with the same heroic musical posture.
Unable to live on the proceeds from his operas, Reyer succeeded Berlioz as music critic at the Journal des débats.