The composer Gaspare Spontini wasn’t known for his modesty.

In 1844, at 70, he traveled to Dresden, Germany, to conduct his opera “La Vestale” at the invitation of the young Richard Wagner. The older composer discouraged Wagner from a career as a dramatic artist, saying that he, Spontini, had brought the art of opera to such heights that any attempt to follow him could only have “ruinous consequences.”

But Wagner later wrote that, despite Spontini’s vanity, the meeting only raised his “high esteem for the master.” Berlioz, too, was a passionate admirer who devoted two chapters to Spontini in “Evenings with the Orchestra.”

In those days, Spontini was at the apogee of the opera world. Yet his reputation faded, along with those of other grand-opera stars.