“Anybody who ever doubted the strength of human will and hard work and will power—oh, my god, I’m amazed at what’s possible.” Linda McInerney might be talking about the title character in the opera she has co-created. Sojourner Truth was indeed a woman of unparalleled determination and capacity for hard work.

And McInerney, who is directing the world premiere of Truth this month in Northampton, does speak of Sojourner in those terms. But right now, during a break in rehearsals, she’s referring to the effort and stick-to-itiveness it has taken to bring this project from the dream stage (in this case, an actual asleep-in-bed dream) to the stage of the Academy of Music.

Sojourner Truth is gradually being recognized as a key figure in American history, “and certainly in the hidden history of women of color,” McInerney says. She was a major force in both the abolitionist and women’s-rights movements of the 19th century, and one of the great orators of her time, despite being unschooled and illiterate. But in the Valley, she’s already a local heroine who lived for some years in a workers’ community in Florence and whose bronze statue stands in a street-corner park there, anchoring a historical district devoted to Truth and the abolitionist community she was part of.

Isabella Baumfree was born into slavery in 1797, not on a Deep South plantation but in New York State, where slaveholding was practiced until 1827. Promised freedom by her owner, who then reneged, she declared her own independence and simply walked away. She took the name Sojourner Truth, a wanderer in the service of spiritual awakening and social justice. In the 1840s she joined the Northampton Association of Education and Industry in Florence, a cooperative founded on principles of equality and religious tolerance. There she met kindred spirits, including the great ex-slave abolitionist Frederick Douglass. And there, as McInerney puts it, “she found her voice.”

I was enslaved, in the house of bondage
And I left, with nothing of Egypt on me
I am on a sojourn in the desert, children,
And God has given me the power to speak.

Truth traces a journey from slavery to freedom, from ecstatic religion to social activism. The opera’s scenario follows her to New York City—where she sued in “the white man’s court” to free her enslaved son, became entangled with a religious cult and was falsely charged with murder—and then along the traveler’s path that brought her briefly to Northampton. The narrative parallels this country’s history from the early republic through the Civil War, when Sojourner recruited black soldiers for the Union army and, incidentally, anticipated Rosa Parks by desegregating the streetcars in Washington, D.C.

At a rehearsal in a Northampton studio, the company is working on music and movement in the sequence surrounding the Civil War. As the cast begins a run-through of a choral number, led by musical director Jerry Noble, McInerney exhorts them to “remember your e-nun-ci-a-tion. And really hit us with that phrase ‘Nation on the brink of civil war!’—powerful, precise, like spitting bullets.” Then, as she listens to the stirring music and lyrics, her eyes are glistening.

The opera—a real sung-through “folk” opera—was created by McInerney, New York-based composer Paula M. Kimper and playwright Talaya Delaney. The all-woman creative team is no coincidence, as McInerney sees the project as a bridge-building exercise, not only “between black and white”—Delaney is African-American—but “between history and what many call herstory.” This month’s premiere is part of the Academy of Music’s ongoing Women’s Work series, dedicated to foregrounding theater by and about women, and incorporating women in all aspects of production. For Truth, the choreographer, choral director, stage and props managers, and lighting, costume and set designers are all women.

And of course the subject and the star are female. Sojourner is played by Evelyn Harris, an alumna of the African-American a capella ensemble Sweet Honey in the Rock, who has become a force in her own right on the Valley music scene since moving here a decade ago. Harris says the woman she’s portraying is “a mega-presence. She’s smart, she’s brave, she’s determined. She walked away [from slavery] without knowing where she was going, how she was going there, but she knew she had to be free. I know that energy. I’ve been around black women like that all my life.”

And she finds climbing into Sojourner’s skin on stage a bit of a challenge. “I know how to interpret a song on stage, but here I’m singing and acting and telling this story at the same time—in a different voice, even. I don’t sound the same as when I do First Night. I’ve tapped into another voice.”

Harris’s rich, supple voice, grounded in folk, gospel, jazz and blues, blends and contrasts with the other leads, who bring classical training to the operatic score. Likewise Kimper’s graceful melodic lines reflect spirituals and folk themes as well as contemporary operatic modes. They flow through Delaney’s hard-edged lyrics, some of which are Sojourner’s actual words.

I could work as well as a man,
And eat as much when I could get it,
And bear the lash as well.
And aren’t I a woman?

Baritone John Thomas, who plays Frederick Douglass, is singing through his speech at an anti-slavery rally: “It is not enough to prevent slavery’s spread—we must wipe out its existence!” He pauses to ask McInerney, “Should I give this straight out front, even though the chorus is behind me?”

“No, no,” McInerney assures him, “when we stage it at the Academy, people will be in the aisles and the stage boxes. They’re cheering you, they’re crazy about you.” She turns to the chorus. “And just before this point, everybody’s at the back of the house near the popcorn.”

Choreographer Lori Holmes Clark is working with Harris on another moment, a public speech of Sojourner’s. On the line “America, your hands are defiled with blood, your fingers with iniquity,” she coaches Harris through a sequence that puts her hands in motion to help reinforce the blood-soaked images.

The opera is full of emotionally wrenching moments, along with uplifting flights of song, and the players are giving heart as well as voice to the work. But the rehearsal makes room for moments of levity, too. One occurs during a tender embrace between Truth and her grandson James, who joins a “colored” regiment in the Union cause. He’s played by tall, dark and handsome Andrew Ward. As he puts his arms around Harris, singing, “Grandmother, are you all right?” she loses her way in the score and forgets her words. McInerney says, “I know, it’s so moving to have that beautiful boy care for you so much.” Harris responds, “That’s not exactly the feeling I had,” and the room explodes with laughter.

Sojourner—my name is Sojourner!
I am a wanderer, and I speak God’s truth.

Truth isn’t McInerney’s first opera. Her Old Deerfield Productions has mounted two previous original works. But this is by far her biggest undertaking, a big-budget epic with a large cast, period-costumed by Jill St. Coeur, expressively lit by Lara Dubin on the Academy’s cavernous stage, and framed by enormous projections of period paintings and photographs, with original graphics by Amy Johnquest. An interracial chorus of 25 supports the lead singers, who include Alan Schneider, Lisa Woods, Amanda Boyd and Wesley Thomas.

This project, McInerney says, has surpassed “my wildest dreams. It’s really astonishing.” The work has been developed over two years from an almost mystical seed, beginning when she awoke one night from a dream with an overpowering image: sitting in the Academy of Music watching Evelyn Harris, in mid-19th-century costume, singing the role of Sojourner Truth.

“To actually see that dream come to life is overwhelming, it’s wild,” McInerney says, adding that what she loves most about the opera “is that everybody involved is so devoted to it. They love the idea of it. I don’t think I’ve ever had this kind of devotion to a piece, ever, because the idea is so deep. People wrap around this woman and what she stands for and stood for and what she accomplished and what she saved.”

Truth: Feb. 16-18, 7:30 p.m., $20-40, Academy of Music Theatre, 274 Main St., Northampton, www.academyofmusictheatre.com, (413) 584-9032 ext. 105.

Chris Rohmann can be reached at StageStruck@crocker.com.