In 1915, Busoni
retired to Switzerland for the duration of WWI, and invited his favorite pupil to assist him in editing Bach
's keyboard works. By this time, Petri had debuted in Holland, Germany, and England (and was professor of music at the Manchester Royal College of Music for six years, 1905 - 1911). In 1920, Busoni
moved back to Berlin, where the Weimar Republic appointed him professor of composition at the Academy of Arts. When Petri came too, Arnold Schoenberg
engaged him at the Hochschule für Musik (1921 - 1926), where his scholarship students included Victor Borge from Denmark. Canadian pianist Gunnar Johansson was another. For many years Petri also taught master classes at the Basle Conservatory. In 1921, he joined Busoni
in a concert of two-piano music at London, and in 1923 became the first foreign-born solo artist to perform in the Soviet Union, so successfully that he played 31 concerts in 40 days.
Petri took up the cause of his mentor's music, including the Brobdingnagian Piano Concerto with chorus and orchestra. At the same time he proselytized on behalf of Liszt
(already out of favor intellectually; his importance and influence were not reevaluated until after WWII), and Bach
of course, in Busoni
's editions and transcriptions. In 1927, Petri moved to Zakopane, Poland, where he lived until 1939. His U.S. debut came when he already was 51 -- in NYC on January 11, 1932 -- followed by touring.
His recording career did not begin until 1929, nor with an orchestra until the prewar London Philharmonic, conducted by Walter Goehr (in the Tchaikovsky
First Concerto) and Leslie Heward (Liszt
's Second and the Fantasy on Beethoven's Ruins of Athens). Stateside, Petri recorded Rhapsodie espagnole with Mitropoulos
and the Minneapolis Symphony
, but otherwise, only solo repertory or chamber music (Brahms
' D minor Sonata in 1937 with Szigeti is legendary). Fortunately, an all-Busoni
program in 1941 by Mitropoulos
and the NYP was broadcast with Petri playing the Indian Fantasy.
When WWII threatened, Petri moved to the U.S. where he became pianist-in-residence at Cornell University (1940 - 1946), and then at Mills College in Oakland, CA, until his death. Darius Milhaud
had been teaching composition there since 1941; John Cage
was in charge of piano accompanying. Petri's notable American pupils included Earl Wild
, who has spoken of his teacher's "quiet tone that was never forced...his playing had a long line instead of stopping to suffer over a phrase." In 1957, Petri revisited Europe for the first time since WWII; finding himself forgotten he returned to the U.S. permanently.