Eugénie "Ninon" Vallin (September 1886 – 22 November 1961) was a French soprano who achieved considerable popularity in opera, operetta and classical song recitals during an international career that lasted for more than four decades.
Eugénie Vallin was born at Montalieu-Vercieu, a small town about 30 miles east of Lyon. She studied at the Lyon Conservatoire and later in Paris. At first she had no intention of performing opera, preparing herself for a career on the concert platform. In 1911 she was chosen by Claude Debussy to sing the part of the celestial voice in the first performance of his Le martyre de Saint Sébastien. She continued her association with Debussy, giving the première of his Trois poèmes de Stéphane Mallarmé in 1914 at the Salle Gaveau in Paris, accompanied by the composer. She also worked extensively with other contemporary composers, including Albert Roussel, Joaquín Nin-Culmell, and Reynaldo Hahn; the latter two accompanied her in recordings of their own works.
She was first persuaded to sing opera in 1912, appearing in a number of roles at the Opéra-Comique, including Micaëla (in Carmen), Mimì (in La bohème), Clara in Les cadeaux de Noël, and the title role in Louise. She went on to make her début at the Teatro Colón, as Marguerite (in Faust) in 1916, returning there regularly over the next 20 years. She made other débuts at Milan's La Scala (in 1916), Rome (1917), the Paris Opéra, as Thaïs, (1920) and San Francisco opera (1934).