Frank London was born June 3, 1958, in the Bronx, to a Reform Jewish family, and grew up in Plainview, New York, and in Connecticut, starting trumpet in the fourth grade. He earned a B.A. in Afro-American music from the New England Conservatory in 1980, the same year he made his recording debut as a sideman on pianist Ran Blake's album Film Noir.

After settling in New York City in 1985, London began working with the all-star downtown ensemble led by bassist and producer Kip Hanrahan (whose orbit also included rock bassist Jack Bruce). Around the same time he started playing Hasidic wedding gigs, learning the style and repertoire of Jewish celebratory music — nigunim, freylekhs, khosidls — from the inside, as working vocabulary rather than folklore. In 1985 he answered a Village Voice advertisement placed by a San Francisco clarinetist seeking klezmer musicians, and through it met singer and accordionist Lorin Sklamberg. The two of them, together with violinist Alicia Svigals, bassist Paul Morrissett, and drummer David Licht, formed the Klezmatics in 1986 — a self-consciously progressive klezmer band built to treat the tradition as living material rather than museum piece, and the group London remains a member of forty years later. Their 1989 debut Shvaygn=Toyt ("Silence=Death," a nod to the ACT UP slogan) announced the band's political and aesthetic stance at once; Rhythm + Jews (1991) and Jews With Horns (1994, the first album with clarinetist Matt Darriau) built the audience that made the Klezmatics the most visible band of the klezmer revival.

London did not confine that revival impulse to one group. With saxophonist Greg Wall he co-founded Hasidic New Wave in the mid-1990s, a harder-edged downtown project that ran Hasidic devotional melody through free jazz and grunge-rock explosions; their studio debut Jews and the Abstract Truth (1997) and the live Live in Cracow (1998) became touchstones of what critics dubbed Radical Jewish Culture. He also leads Frank London's Klezmer Brass Allstars, a Balkan- and Ottoman-inflected party band whose Brotherhood of Brass (2002) brought together Serbian Romani trumpeter Boban Marković's orchestra and Cairo's Hasaballa Brass Band on one record, and whose Carnival Conspiracy (2005) won a German Record Critics' Award. Earlier in his career he co-founded the New Orleans-style Les Misérables Brass Band and was an original member of the Klezmer Conservatory Band. He teaches at SUNY Purchase and serves as Artistic Director of KlezKanada, and has led klezmer workshops from the Catskills to Crimea.

The connective thread across all of it is John Zorn. London recorded repeatedly for Zorn's Tzadik label as part of its Radical Jewish Culture series — The Debt (1997), Nigunim (1998, a trio with Sklamberg and pianist Uri Caine), Invocations (2000), Scientist at Work (2002), Hazónos (2005), Tsuker-zis (2009, a duo with Sklamberg), and 2024's Brass Conspiracy among them — with Zorn frequently serving as executive producer. He plays trumpet in Zion80, guitarist Jon Madof's ensemble that recasts Zorn's Masada songbook in Afrobeat rhythm (Adramelech: Book of Angels Volume 22, 2014, Tzadik), and Hasidic New Wave's five-disc Complete Recordings was reissued on Tzadik in 2012 with Zorn again as executive producer. John Zorn is profiled separately on jazzprofiles.com/profile/john-zorn; London's decades in Zorn's orbit are one of the clearest bridges in this system between klezmer and the jazz avant-garde.

London's output extends well past records into theater, dance, and film. He composed the score for The Shvitz (Jonathan Berman's 1993 documentary on New York's last Jewish bathhouses), scored John Sayles' films The Brother from Another Planet (1984) and Men with Guns (1997), and wrote Davenen for Pilobolus Dance Theatre (excerpted on the Klezmatics' Rise Up! = Shteyt Oyf!, 2002). His folk opera A Night in the Old Marketplace (2007), adapted from I.L. Peretz's 1907 Yiddish play with a book by Glen Berger, was described by critics as Kurt Weill and Bertolt Brecht filtered through klezmer and rock; his earlier musical Green Violin, about Soviet Yiddish theater, won the 2003 Barrymore Award for Best New Musical. He also served as conductor and music director for a production of David Byrne and Robert Wilson's The Knee Plays. On record, the Klezmatics reached their widest audience by setting previously unpublished Woody Guthrie lyrics to new music at the invitation of Nora Guthrie and the Woody Guthrie Foundation: Wonder Wheel: Lyrics by Woody Guthrie (2006) won the Grammy Award for Best Contemporary World Music Album at the 49th Grammy Awards in 2007, and a companion record, Woody Guthrie's Happy Joyous Hanukkah, followed later that year. He has also turned up, as a working session trumpeter, on records by They Might Be Giants, Ben Folds Five, Marc Ribot, Natalie Merchant, and on the official soundtrack album for HBO's Sex and the City.

London remains prolific into his late sixties: Ghetto Songs (Venice and Beyond) (2021) marked the 500th anniversary of the Venice Ghetto, the walled quarter whose name gave the word its modern meaning; In the City of God (2024) set new melodies for Simchat Torah dancing; and Brass Conspiracy (2024, Tzadik) grew out of a commissioned score for choreographer Jody Oberfelder. That same year he released Spirit Stronger Than Blood with his quartet the Elders, made and dedicated, in his own words, as "a celebration of life" after being diagnosed with myelofibrosis, a rare blood cancer; the album carries dedications to departed friends and collaborators including trumpeter Lester Bowie and cornetist Ron Miles. A new project, Frank London & the Loisaida Fife and Drum Corps, is set to release Touzle Your Kurchy on Adhyâropa Records in late August 2026. Called the "mystical high priest of Avant-Klez jazz," London has made more than 30 solo recordings and is credited on well over 400 releases; in 2025 he was inducted into the Manhattan Jewish Hall of Fame.

London's music runs on a single conviction: that klezmer is not a museum genre but a living language, and that language survives by being spoken in unfamiliar rooms. He learned its grammar first-hand playing Hasidic weddings in the 1980s, then spent the following decades running that vocabulary through everything else he knows — the free-jazz and no-wave language of downtown Manhattan (via Kip Hanrahan, John Zorn, and the Knitting Factory scene), Balkan and Ottoman brass-band tradition (via Boban Marković and the Hasaballa Brass Band), Afrobeat (via Zion80), cantorial and liturgical repertoire (Hazónos, In the City of God), and American vernacular song (the Klezmatics' Woody Guthrie project). As a trumpeter he favors a big, vocal, cantorial tone that can turn instantly rough and declamatory; as a bandleader and arranger he is drawn to large, polyglot ensembles — brass bands doubled with Balkan Romani horns, klezmer quintets doubled with gospel choirs — that make the boundary-crossing audible rather than theoretical. Critics have called him the "mystical high priest of Avant-Klez jazz," a title that captures both the seriousness with which he treats the tradition and his refusal to leave it alone.