Who is Dave Van Ronk? Many are bound to ask after screening the Coen brothers' Greenwich Village-set "folk"-tale Inside Llewyn Davis. Oscar Isaac stars as Davis, a character loosely based on the real-life journeyman folk singer Van Ronk.

While a more precise and complete account of Van Ronk's life can be found in Elijah Wald's 2005 biography The Mayor of MacDougal Street, the folk boom of the early 1960s depicted by the Coens is already the stuff of legend, and Van Ronk was certainly in the thick of it all. Born in Brooklyn in 1936, he came to Greenwich Village in the late 1950s and became a regular at the musical gatherings in Washington Square Park, which then spilled into the neighboring coffeehouses and pubs, and finally, for a select few, into recording booths, TV studios and major concert venues.

More of a bluesman and jazz singer than a folkie per se, Van Ronk's own music can be found on Down in Washington Square, a solid three-disc set highlighting both the strong beginning and dignified end of Van Ronk's career in song. "Dave was not as much of a songwriter as an interpreter of jazz and blues and other songs that he liked," says Jeff Place, compiler and annotator of the new Smithsonian Folkways collection. "He was also surrounded by songwriters, and Dave was the first person to ever record a song by Joni Mitchell."

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Musically, Dave Van Ronk was influenced by iconic folk-bluesmen, including Josh White, Mississippi John Hurt and Reverend Gary Davis, as well as empathic jazz entertainers like Bessie Smith, Billie Holiday and Jelly Roll Morton. Never fated for stardom, he was at once a typical denizen of the burgeoning folk scene and a distinctive entertainer/song stylist of real influence. Singing in a raspy, gruff-or-tender growl, he was a singular guitarist who arranged his chosen performance material quite carefully.

Dave was especially deep into songs from earlier times, including the folk, blues and country tunes on the classic compendium The Anthology of American Folk Music, organized by Harry Smith and released in 1952. Smith's anthology was a cultural touchstone of the early folk scene, and his selections included Depression-era blues, Appalachian folk songs and recycled ballads of the British Isles. "The effect of The Anthology of American Folk Music was huge," says Place. "Those songs, and being the devotees of that music, people like Dave were the gate-keepers -- and they would pick up these old songs like ‘House of the Rising Sun.' "

Indeed, the best known Van Ronk story involves a young Bob Dylan pinching a splendid arrangement of "The House of the Rising Sun" for his 1962 debut album before Van Ronk could record it himself. Ironically, Van Ronk first heard the old song of New Orleans woe on a field recording made by Harry Smith's archival rival, Alan Lomax. Ouch.

Just one folk-generation after Ramblin' Jack Elliott (that's two behind Woody Guthrie, and five years older than Bob Dylan), Van Ronk found himself in the midst of a Village folk scene on the verge of going mainstream. The ambitious Van Ronk came along a full decade after the first Washington Park gatherings and pushed his way in among an impressive arrangement of resourceful performers. Some might be thrilled just to show up on the pages of Sing Out!, but others were eager to end up on television programs like Hootenanny, or better yet, finagle a contract with a label like Elektra or Folkways Records.

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While never really commercially oriented, Van Ronk's near miss as a member of Peter, Paul & Mary was probably more of a mutual decision than due to his basic unwillingness to sell out. Still, groups like PP&M stayed busy patronizing, as did other ersatz folk ensembles like The Kingston Trio and The New Christy Minstrels -- all parodied so well in the 2003 comedy A Mighty Wind.

There's another new three-disc collection that contextualizes the world of Van Ronk. Live From Caffe Lena: Music From America's Legendary Coffeehouse (1967-2013) has only one Van Ronk performance, but it places him alongside notable folk icons including Jean Ritchie, Mike Seeger, Utah Phillips and Ramblin' Jack Elliott as well as Woodstock-based singer-songwriters like Happy & Artie Traum. Lena's Saratoga Springs locale is almost 200 miles upstate from Greenwich Village, but the folk community that performed there still comes shining through.

Dave Van Ronk died in 2002, but always went his own way. He remained a solid guitarist, an insightful interpreter, a savvy entertainer and a local hero. He was a folk survivor like Pete Seeger, Tom Paxton and Judy Collins -- and like other Village old-timers, he had his own "Bobby Dylan slept on my couch" story. He stood firm as the Mayor of MacDougal Street -- a patron saint to Greenwich Village musicians and a mentor to many singer-songwriters over the years.

Bouncing from one music label to another, Van Ronk rarely decided to "go electric." He made numerous recordings -- live and in the studio -- and maintained his stylistic idiosyncrasies throughout. Whether it was a bluesy imagining of "God Bless the Child," a plaintive rendition of "Chelsea Morning," a razor-sharp "Cocaine Blues" or a ragtime guitar rendition of "The Entertainer," Van Ronk spent his life recontextualizing the great American songbook from a most distinctive vantage point … not too far from the corner of Bleecker and MacDougal.