Whoever and whatever "St. Stephen" is actually about is somewhat more cryptic than it may appear. Generally, two different men have been batted around as likely subjects of the song.
For a long time, many fans believed the song was about Stephen Gaskin, a prominent counterculture and spiritual figure in the Haigh Ashbury during the 1960s when the Dead lived there. In 1971 Gaskin left the West Coast to start a commune near Summertown, Tennessee. The commune was named "The Farm" and was one of the most prominent communities of its kind. As of 2018, it still exists (though in a different form than the one in which it was founded). Knowing Gaskin's "saintly" attributes and the Dead's proximity to him, it's easy to see how products of that time and space made this connection, but this interpretation was always more on the fringe than the other one.
The vast majority of listeners over the years believe "St. Stephen" to be about the first martyr of Christianity, a 1st century deacon who preached a version of Christ's teachings that angered many other religious leaders of his time ("wherever he goes the people all complain").
The real Stephen was stoned to death after being tried by authorities. Paul the Apostle, one of the most important figures in the New Testament, witnessed Stephen's martyrdom. Acts 6:8–10 reads: "Now Stephen, a man full of God's grace and power, performed great wonders and signs among the people. Opposition arose, however, from members of the Synagogue of the Freedmen (as it was called)—Jews of Cyrene and Alexandria as well as the provinces of Cilicia and Asia—who began to argue with Stephen. But they could not stand up against the wisdom the Spirit gave him as he spoke."
So, the Biblical Stephen seems like a slam dunk as the Dead's "St. Stephen," but Robert Hunter, who wrote the lyrics to the song, muddied the waters in various interviews. When Relix asked if the song was about "anyone specific," Hunter responded, "No, it was just Saint Stephen."
Also, while talking to author/historian Jeff Tamarkin, Hunter said, "I had been working on this a long time before I gave it to the Grateful Dead, before I took off for New Mexico, which is where I originally sent them the lyrics from. I don't know what to say about this song, except that it was very important to me. It seemed to be saying oodles. It's still one of my favorite. I didn't know who the real Saint Stephen was until I wrote it."
Still, despite Hunter's somewhat elusive comments, the song's lyrical content is so similar to the story of the martyred Stephen that it's hard to believe that the song's about anyone else, though perhaps Hunter took some poetic license with the story and was talking about things more archetypal or abstract than a literal historical biography.
The Dead opened their 1969 Woodstock performance with "St. Stephen." The band's set ran from late Saturday night (August 16) into Sunday morning (August 17). Dead frontman Jerry Garcia later said he was disappointed and frustrated with their set. Too many drugs, drinks, rain, mud, and equipment malfunctions (including instruments that delivered small electric shocks to the band as they played) all created a frustrating and disappointing performance. With "St. Stephen," however, the band seemed to come out the gate pretty strong, and now that it's widely available, many fans hold the performance in higher esteem than Garcia did.