Harold Bauer was born in Kingston upon Thames; his father was a German violinist and his mother was English. He took up the study of the violin under the direction of his father and Adolf Pollitzer. He made his debut as a violinist in London in 1883, and for nine years toured England. In 1892, however, he went to Paris and studied the piano under Ignacy Jan Paderewski for a year, though still maintaining his interest in the violin. An anecdote reports that Paderewski jokingly told Bauer to concentrate on the piano because "You have such beautiful hair". In 1893, in Paris, he and Achille Rivarde premiered Frederick Delius's Violin Sonata in B minor.
During 1893-94 he travelled all through Russia, giving piano recitals and concerts, after which he returned to Paris. Further recitals in the French capital brought him renown, and he almost immediately received engagements in France, Germany and Spain. His reputation was rapidly enhanced by these performances, and his field of operation extended through the Netherlands, Belgium, Switzerland, England, Scandinavia and the United States.
On 18 December 1908, he gave the world premiere performance of Claude Debussy's piano suite Children's Corner in Paris. After that he settled in the United States, and was a founder of the Beethoven Association.
In later life, he became the principal piano teacher at the well known Manhattan School of Music, and was known for his master classes. Today, the Harold Bauer Award is given to promising pianists at the school. From 1941 until his death, Bauer taught winter master classes at the University of Miami.
Bauer was married twice. He had been married to Marie Knapp (1873–1940) until her death. Sometime between 1940 and 1943, Bauer married again, to concert pianist, colleague, and former student Wynne Pyle. He had no children by either marriage.
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- Volume 2: August 1949–August 1952 (1953)
- Volume 3: September 1952–August 1955 (1956)
- Volume 4: September 1955–August 1958 (1960)
- Volume 7: September 1964–August 1967 (1968)
- Volume 8: September 1967–August 1970 (1971)
- Volume 9: September 1970–August 1973 (1974)
- Volume 11: September 1976–August 1979 (1980)
- Volume 12: September 1979–August 1982 (1983)
- Volume 16: September 1988–August 1990 (1990)
- Volume 21: September 1995–August 1996 (1996)
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- Free scores by Harold Bauer at the International Music Score Library Project
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