Born in
Hopewell, New York, Walker had her initial musical training at her church in her native town where she sang in the choir and began performing solos at the age of 14. Her family moved to
Rome, New York, where she graduated from
Rome Free Academy in 1884 and continued to be active as a soloist at her church. After teaching for several years, she entered and won a singing competition which provided her with a scholarship enabling her to study singing in Europe. She arrived in Dresden, Germany, in 1891 where she became a pupil of
Aglaia Orgeni. She later studied singing with
Marianne Brandt in Vienna. Walker made her professional debut as a concert singer at the
Gewandhaus in Leipzig in 1892. She made her professional opera debut on 11 November 1894 at the
Berlin State Opera as Fidès in
Giacomo Meyerbeer's
Le prophète. The following year she became a member of the
Vienna State Opera where she was a leading mezzo-soprano with the company for eight seasons. She notably sang the role of Magdalena in the Vienna premiere of
Wilhelm Kienzl's
Der Evangelimann in 1896. She was also much admired in Vienna for her interpretation of the role of Amneris in
Giuseppe Verdi's
Aida. While under contract in Vienna, Walker made guest appearances with other European theatres. She made her first appearance in the UK at the
Royal Opera House in London, singing the role of Amneris on 16 May 1900. She sang several more roles at Covent Garden in 1900–1901, all of them from the Wagnerian repertoire, including Erda in
Siegfried, Fricka in both
Die Walküre and
Das Rheingold, Ortrud in
Lohengrin, and Waltraute in
Götterdämmerung. In 1901 she portrayed the role of Elvira in
Wolfgang Amadeus Mozart's
Don Giovanni at the
Salzburg Festival. ==Metropolitan Opera years and later career==