Koenig was born November 30, 1963, and grew up in tiny Englefeld, Saskatchewan, Canada. He was mentored musically by his older brother Mark, a violinist, and when he was 15, Robert moved to Vancouver, British Columbia, for studies at the Vancouver Academy of Music. His teachers there were Lee Kum-Sing and Gwen Thompson. He lived with his brother, who was already living in Vancouver. Supported by several grants from the Canadian government, he went on to the Banff School of Fine Arts in Albert and then to the Academie Musicale di Chigiana in Siena, Italy. Koenig earned bachelor's and master's degrees at the Curtis Institute in Philadelphia, studying with Vladimir Sokoloff, and also taking chamber music classes with Felix Galimir and Karen Tuttle. Koenig served as staff pianist at the Curtis Institute of Music and the Juilliard School, and in 2000, he became professor of piano and piano chamber music at the University of Kansas. The following year, he backed John Rojak on the MMC album The Romantic Bass Trombone. While at Kansas, he commissioned composer Lowell Liebermann's Trio for flute, cello and piano, Op. 87, and premiered the work at the National Flute Association Convention in Nashville, Tennessee.
Parallel to his teaching career, Koenig has been an active performer who has appeared at Carnegie Hall in New York, Kennedy Center in Washington, and Suntory Hall in Tokyo, among other major world halls. He has backed such major violinists as Hilary Hahn, Sarah Chang, and Augustin Hadelich, and he has had ongoing associations with Elmar Oliveira and the late Aaron Rosand. In 2007, Koenig moved to the University of California at Santa Barbara, where he serves as professor of piano and head of the collaborative piano department. He has appeared on recordings on Decca, Cedille, CRI, and other labels. Koenig's 2006 recording of William Primrose's transcriptions for viola and piano, with violist Roberto Díaz, was recorded for Naxos and earned a Grammy nomination for Best Instrumental Solo Performance. He has continued to record for various labels, and in 2022, he backed cellist Jennifer Kloetzel on an Avie recording of Beethoven's complete sonatas for cello and piano. ~ James Manheim, Rovi