Kiesler was born in New York on August 18, 1953, and grew up studying music from a young age. He sang in choirs and played the trumpet, and he soon developed an interest in conducting, leading his first concert at age 15 as a substitute for an ailing director. Kiesler attended the University of New Hampshire, studying conducting and music history, and at 19, he led the first performance since 1925 of the original jazz band score of Gershwin's Rhapsody in Blue. He went on for a master's in orchestral conducting at the Peabody Conservatory at Johns Hopkins University in Baltimore. From 1980 to 2000, he served as the music director of the Illinois Symphony, where he remains conductor laureate. Kiesler also served as the assistant conductor of the Indianapolis Symphony from 1980 to 1983, music director and conductor of the South Bend Symphony Orchestra from 1984 to 1988, principal conductor of the Saint Cecilia Orchestra from 1992 to 1995, and principal conductor of the New Hampshire Symphony Orchestra from 2002 to 2007. The list of orchestras he has guest conducted is extensive and worldwide in scope, including the Chicago Symphony, the National Symphony in Washington, and the Pusan Symphony Orchestra in Korea. In 1995, he joined the conducting faculty at the University of Michigan, where he continues to serve as professor of conducting and director of orchestras, often leading world premiere performances. Kiesler founded the Conductors Retreat at Medomak, an intensive program for young conductors, in 1997.
Kiesler has made more than ten recordings for Naxos, Dorian, and other labels, issuing several albums in the former label's American Classics series. In 2010, he led the University of Michigan Symphony Orchestra in the premiere recording of Evan Chambers' The Old Burying Ground. Kiesler's 2014 recording of Milhaud's L'Orestie d'Eschyle with the University of Michigan Symphony was nominated for a Grammy award. In 2021, he conducted the same group in a recording of music by Vítezslava Kaprálová. ~ James Manheim, Rovi