SOMERVILLE — Midway through her sold-out show Thursday at Arts at the Armory, the songwriter Anaïs Mitchell noted that the room was full of old friends and family. Her high school sweetheart was somewhere in the audience, she said.
She began to tell a story about a bus trip they once took from her native Vermont into the big city of Manhattan, where they got lost. She certainly knows her way around New York City now: Mitchell’s “Hadestown,” a folk opera based on the Greek myth of Orpheus and Eurydice, opened on Broadway last April. In June, it won eight Tony Awards.
Thursday’s show was a homecoming of sorts for Mitchell, who was inspired to become a singer after discovering Cambridge’s Club Passim. She worked out “Hadestown” at the Somerville Theatre years before the show began its steady ascent toward Broadway.
Reminders to be present in the moment recurred throughout the night. Mitchell mentioned that she’d marveled at the fall foliage on the drive up from her home in Brooklyn, something she said she never noticed growing up in Vermont.
“I’m such a tourist now,” she joked.
On her song “Morning Glory,” written for her daughter, Ramona, who is now 6, she sang about the wonder of waking up to a child who’s already itching to start the day.
“How long have I been sleeping?” she sang from the bare stage, below a string of lights.
Opener Mark Erelli contributed to the theme with his gorgeous song “Look Up,” about a custodian working at the Sistine Chapel. He also played his recent release “By Degrees,” a lament for the country’s gun violence epidemic. With guests including Mitchell, Rosanne Cash, and Lori McKenna, the song was nominated as the Americana Music Association’s Song of the Year.
Mitchell, playing a ¾-scale acoustic guitar and accompanied by fellow guitarist Austin Nevins, played several songs from her 2012 album, “Young Man in America,” including the deeply affecting “Shepherd,” an ode to her father, and “Tailor,” an aching lost-love song. She also sang “Bonny Light Horseman,” an old English folk song with a title Mitchell has borrowed for the name of her latest project, a collaboration featuring Eric D. Johnson and Josh Kaufman.
But the most enthusiastic response came, unsurprisingly, for the songs from “Hadestown” — “a musical I’ve been working on for one-third of my life,” Mitchell said, in case anyone in the room was unaware. In the middle of “Wedding Song,” she veered off into a few verses of Gillian Welch’s “Elvis Presley Blues.” Nevins, who’d been humming a countermelody, didn’t flinch. It’s a song they used to play together when he lived in Somerville, she explained when they finished.
Like other key songs from her musical, “Why We Build the Wall” was written back in 2006, she explained. A dark allegory about fear of the other, “I never dreamed it would feel this relevant,” Mitchell said, “and I hope it doesn’t feel this way for long.”
Welcoming Erelli back to the stage, Mitchell and Nevins ended the evening with a humble version of “Deportee,” Woody Guthrie’s song about the anonymity of the immigrant experience. Singing off-mic, they highlighted the timelessness of Mitchell’s folk roots, which are, as it happens, perfectly timed to the present.
With Mark Erelli. At Arts at the Armory, Somerville, Oct. 10James Sullivan can be reached at firstname.lastname@example.org. Follow him on Twitter @sullivanjames.