It’s no more accurate to say that Chris Strachwitz “discovered” Clifton Chenier than to say Christopher Columbus “discovered” America: The king of zydeco had thrived within an insular local scene long before the outsider came along. But unlike Columbus, Strachwitz had an unambiguously positive impact on his “discovery,” transforming the singer-accordionist from a Gulf Coast dancehall hero into an international festival star. And Strachwitz made dozens of such discoveries—introducing such heroes as Lightnin’ Hopkins, Robert Randolph, Country Joe McDonald, Mance Lipscomb, the Savoy Family Band, Flaco Jiménez, Beausoleil, Dewey Balfa, and the Campbell Brothers to a much wider audience.

Strachwitz’s vehicle was his independent label, Arhoolie Records, which celebrates its 50th anniversary this month. (Actually, 2010 was the company’s 50th, but like most shoestring operations, it has trouble meeting deadlines.) To mark the occasion, Arhoolie is not releasing a five-CD, historical-overview box set; it did that quite successfully for its 40th birthday. Instead Strachwitz has dug up his earliest field recordings and documented them in two packages: Hear Me Howling! Blues, Ballads & Beyond, a 136-page coffee-table book accompanied by 72 songs on four CDs, and Down Home Music: A Journey Through the Heartland—1963, a 75-minute DVD. Most of the music tracks and film footage has never been issued in the U.S., and they capture a time when roots music was still a new concept, when hundreds of local scenes remained unknown to outsiders, when a young enthusiast could drive through East Texas and find Lightnin’ Hopkins singing on a Houston street corner or Mance Lipscomb singing on dusty dirt road.

Today Hopkins and Lipscomb are considered giants of Texas musical history, but in 1959 Hopkins was just a name on some hard-to-find blues records and Lipscomb was barely known at all. Following a tip that Hopkins was living in Houston, Strachwitz, a 28-year-old German immigrant living in the Bay Area, traveled by bus and car to find out if it was true. Strachwitz was so stunned by the wiry man in the pork pie hat and shades that he resolved to start his own label. On that same trip he made the first-ever recordings of Lipscomb, not so much a bluesman as a brilliant “songster” like Leadbelly. Those became the first Arhoolie release a year later.

Four years later Strachwitz returned to Texas with German documentary filmmaker Dietrich Wawzyn. They filmed Lipscomb singing “Goin’ Down Slow” in his white fedora on his front porch and Hopkins shooting craps and singing “Lonesome Road Blues” on a Houston sidewalk. It was part of a summer-long trip that took the two men from a blues club in San Francisco to a gospel service in Phoenix to a Cajun dance in Louisiana to a jazz funeral in New Orleans to hillbilly shack in Mississippi to a recording session in Nashville to a bluegrass band in North Carolina. Originally shot for German TV, the black-and-white footage has been re-edited into Down Home Music.

The music on the four CDs in Hear Me Howling comes from field recordings Strachwitz made in the Bay Area between 1954 and 1971. When performers came through the area, the budding engineer would tape them at a show, at a party, or in somebody’s home—often Strachwitz’s own. He wound up with more material than he could release at the time. Some of the leftovers, collected for the first time, are stunning. The highlights include three songs that Big Joe Williams recorded right after being released from the psychiatric wing at the Alameda County Jail; bluesman Bukka White’s 11-minute, impromptu fantasia “Bald Eagle Train”; Rev. Gary’s Davis’s ferocious set at a Berkeley coffeehouse in 1964; Skip James’ high-tenor-and-solo-piano recordings from 1965; and Clifton Chenier’s “Mr. Charlie,” the story of a house fire. It all makes for a fascinating document, confirming there’s still material to be tapped from the reservoirs of American roots music.