"The Long Steel Rail" by Norm Cohen has an extensive history of this song from which we quote the following excerpts:

"This 1950s favorite of the folksong revival has always been associated with the great black folksinger Huddie Ledbetter (Leadbelly), who, though he did not originate it, is unquestionably responsible for its popularity.

The song was first collected by John Lomax in 1934 on one of his tours of state prisons through the South searching for folk songs. He recorded it twice, first from a group of black convicts in Little Rock, Arkansas, and shortly thereafter from another group of black convicts lead by Kelly Pace, at Cummins State Farm, Gould, Arkansas. Lomax was told it was an Arkansas song and did not find it elsewhere. Leadbelly was employed as Lomax's chauffeur, and this was doubtless when he first heard 'The Rock Island Line'.

Leadbelly first recorded 'Rock Island Line' in June, 1937, for the Library of Congress in Washington, D.C. That selection, the text of which is transcribed here, has since been released on L.P. His spoken introduction of the song describes the log cutting that the song accompanied when he, with Lomax, heard it in Arkansas. In June, 1940, he recorded the song for RCA Victor with the Golden Gate Quartet, this time unaccompanied and without spoken introduction. In January, 1942, he recorded it a third time for Moses Asch, who subsequently released the piece on two of his 78 rpm labels, Asch and Disc. By now Leadbelly had begun to work out the spoken introduction about livestock and pig iron that we now think of as an integral part of the song. By the time of his fourth recording, for Capitol Records in Hollywood in October, 1944, (transcribed here) the introduction was nearly complete. It still lacked the final rejoinder of the engineer, who signaled to the depot agent, as his train gathered steam and disappeared from sight.

I fooled you, I fooled you I got iron I got all pig iron, I got all pig iron

This part appeared on Leadbelly's recording for Moses Asch, probably 1944-46, issued on Folkways FP14 (subsequently renumbered FA 2014): 'Rock Island Line'. During the last few years of his life, Leadbelly recorded the song again and performed it regularly at his numerous concerts and on various radio programs thus exposing people throughout the country to what was once strictly an Arkansas work song.

After Leadbelly's death, the song was picked up by other influential performers in the awakening folksong movement: English singer Lonnie Donegan recorded it in 1956 and had a hit on both sides of the Atlantic (it climbed to number ten of Billboard's pop charts that March) and it was later recorded by such successful artists as the Weavers, Odetta, the Tarriers, the Gateway Singers, and the Rooftop Singers."

Whew!!!