Robert Johnson did not invent the blues. By the time he was born in May 1911 to Julia Major, the music had existed, in some form or another, for half a century, its forlorn spirit first documented in the early days of the American Civil War. And down in the Mississippi Delta, Johnson was able to learn, borrow, or even steal from some of its best apostles, famously including Son House and Skip James. But Johnson’s personal tragedy—allegedly poisoned to death in 1938 at a gig, a year after Vocalion began releasing 78s from a few quick Texas sessions—became his slow-moving and posthumous professional triumph. When Columbia released King of the Delta Blues Singers in 1961, nearly nothing was known about Johnson, so people simply bought whatever myth they heard. Selling his soul at the crossroads, poisoned by an ill-hearted lover, Robert Johnson became the blues incarnate. By the time Columbia issued Vol. II of that set in 1970, Johnson’s music had not only helped spawn blues-rock and the British Invasion, it also inspired new questions about who he was and what he’d been through. As more answers emerged, so did more questions and myths. Curiosity ballooned. And finally, in 1990, after decades of legal wrangling with dogged Johnson scholar Mack McCormick, Columbia finally did its best to answer everything it could by releasing almost every known Johnson performance—29 distinct songs, 41 takes, and a book that tried its best to set the facts of Johnson’s life straight. The double-disc set improbably sold a million copies in less than four years, a testament to Johnson’s influence and the endless intrigue of the unknown. But as Keith Richards wrote of Johnson’s “Love in Vain” in the liner notes: “It was just so beautiful: the title, the lyrics, the ideas, the rhymes, just everything about it.” The music Johnson left behind outstrips any speculation. With its stuttering riff and sparkling notes, “Terraplane Blues” is a fit of mischief about a lover who’s been stepping out. Digging against the strings like they hold the key to salvation, Johnson presents in “Cross Road Blues” a plea for spiritual help—even if he has to drop to his knees and beg. And the spry guitar melody and the ebbing tide of Johnson’s voice testifies to earthly toil, to the enemies that have “overtaken poor Bob at last” or those who are “tryin’ to take my life and all my lovin’, too.” Johnson’s own history would soon make such songs seem prescient of his doom; in the decades to come, however, rock history would turn them into glory, no matter how hard the facts were to find. Johnson died in 1938, when he was just 27, establishing an infamous rock ’n’ roll fraternity. But there remain enough ideas in these 29 songs—his ability to harmonize with himself, to make six strings sound like a full band, to conjure joy and suffering in what seemed like tossed-off quips—to last several lifetimes, exactly as they have.