On Christmas night 1895, at Bill Curtis’s notorious St. Louis saloon, a gun-toting carriage driver named Lee Shelton shot and killed his friend William Lyons. According to an account of the incident in the St. Louis Globe-Democrat, “an argument was started” between the heavy-drinking hotheads, “the conclusion of which was that Lyons snatched Sheldon’s [sic] hat from his head. The latter indignantly demanded its return. Lyons refused, and Sheldon drew his revolver and shot Lyons in the abdomen. … When his victim fell to the floor Sheldon took his hat from the hand of the wounded man and coolly walked away.”

That night, a man died and a legend was born. Shelton—alias Stack Lee—would be memorialized in song, becoming perhaps the most significant figure in African-American folklore. In a 1911 article in the Journal of American Folklore, the sociologist Howard W. Odum presented several versions of the song, which he’d been collecting throughout the American South:

Stagolee killed a man an’ laid him on de flo’,
What’s dat he killed him wid? Dat same ole fohty-fo’.
Oh dat man, bad man, Stagolee done come.

Mississippi John Hurt, Cab Calloway, Woody Guthrie, James Brown, Wilson Pickett, Tina Turner, Bob Dylan, and Beck are among the hundreds who have sung a version of Stagolee’s story. Lloyd Price took a rollicking rendition of “Stagger Lee” to the top of the pop charts in 1959. Such brushes with mainstream success never compromised Stag’s street cred, though. In bars, barbershops, and prisons, he remained “the baddest n—– who ever lived,” the antihero of profane epics and rhyming “toasts” whose exploits offered a fantasy of freedom from life’s indignities. Stagolee haunts the prose of Richard Wright and Toni Morrison; James Baldwin worked on a novel about the character and late in his life published a long poem called “Staggerlee Wonders.”

Scholars of African-American studies generally agree that both the pimp protagonists of  ’70s blaxploitation films and the self-mythologists of gangsta rap are Stagolee’s direct descendants: mononymous, fearless, and fastidious about their name-brand apparel. In their New Book of Rock Lists, Dave Marsh and James Bernard name 15 “Sons of ‘Stagger Lee’—Records That Would Be Inconceivable Without Him,” including the Geto Boys’ “Mind of a Lunatic,” Cypress Hill’s “How I Could Just Kill a Man,” and Ice Cube’s “The N—a You Love to Hate.”

Despite the tendency of folktales to grow taller, the canonical Stagolee story has remained impressively stable over the years: Stagolee is a “bad man” who objects to Billy Lyons’s stealing his Stetson. Billy pleads for his life, invoking his wife and young children, but Stag pitilessly executes him, usually with a .44. It’s strikingly close to what actually happened, right down to the names of the principals and the caliber of the murder weapon. Turn-of-the-century St. Louis was a musical place—the cradle of ragtime, full of “barroom bards” and river roustabouts who were constantly turning scuttlebutt into song. It was not unheard of, in other words, for the day’s news to pass from fact into folklore almost instantaneously, trapping many authentic details in the amber. The events that inspired the murder ballads “Frankie and Johnny” and “Duncan and Brady” occurred within a few years, and a few blocks, of the Stagolee killing.

What about Stag’s “bad man” reputation and Billy’s wife and children, though? Researchers have tended to conclude that those two elements of the myth are songwriters’ embroideries. Lee Shelton had no prior criminal record that anyone could locate, and William Lyons was listed as single on his death certificate. But over the past several years, through services like Newspapers.com and Ancestry.com, huge caches of relevant documents have become broadly available—and, crucially, keyword-searchable—for the first time. A couple of summers ago, I started poking around in those collections, and once I started comparing what I thought I knew about the Stagolee legend with what I was seeing in the documentary record, I found that I couldn’t stop.