Friedlaender emigrated to America in 1911 where he taught at Harvard University. He succeeded Rochus von Liliencron as general editor for a Book of National Songs for Men's Choirs first proposed by Kaiser Wilhelm II in 1906. In the 1920s, Friedlaender was closely involved in the formation of the Deutsches Volksliedarchiv (German folksong archive). The Nazi regime popularized the archive's work in keeping with its nationalist cultural policies – ironic given Friedlaender's Jewish heritage.
Works
Friedlaender's edited several popular song anthologies for the Leipzig music publisher CF Peters including works by Robert Schumann, Felix Mendelssohn, Carl Loewe, Ludwig van Beethoven, seven volumes of Schubert songs, a collection of folk songs, and a "Choral Manual." Some of these editions are still in print today. In his researches, Friedlaender discovered several previously unknown songs by Schubert. His magnum opus is a two-volume study of German song in the 18th century (Cotta, Stuttgart 1902).
Literary works
1885: 100 Deutsche Volkslieder (100 German folk songs)
P. V. Bohlman, Landscape - Region - Nation - Reich; German Folk Song in the nexus of National Identity, in Celia Applegate (Ed.), Music and German National Identity (University of Chicago, 2002).