What does war sound like?

It depends upon your proximity to it. It can sound like the chaos and carnage of the battlefield. It can sound like the rhythmic roar of protest. It can sound like the austere brass of ceremony or the deafening silence left by those we’ve lost, the space we save for memory.

“Unknown,” a new song cycle from composer Shawn Okpebholo and poet Marcus Amaker, attempts to examine war from every angle at once. And in succeeding, it offers a new mode of memorial and a reimagined take on what makes a piece of music patriotic.

Composed to commemorate the centennial of the Tomb of the Unknowns at Arlington National Cemetery, “Unknown” uses its five movements to inhabit multiple perspectives (including a soldier preparing to deploy, a son mourning his fallen father and a Tomb guard) and seamlessly shift through musical modes.

The cycle premiered last month at the Barns at Wolf Trap, but a streaming cinematic presentation of the work from director Kristine McIntyre is set to premiere on Veterans Day, Nov. 11, the official centennial of the Tomb, at urbanarias.org.

“Unknown” was co-commissioned by a broad coalition of opera companies led by the Arlington-based UrbanArias (and including Wolf Trap Foundation for the Performing Arts, Opera Colorado, Minnesota Opera, the Dallas Opera and Opera Birmingham), but the work is a direct and distinct product of the creative chemistry between Okpebholo and Marcus.

When UrbanArias founder Robert Wood contacted Okpebholo about the idea, the chronically busy composer came close to turning it down, but something about the Tomb weighed heavy on his mind.

“This appealed to me because it was something different, but it’s also something we can all relate to,” Okpebholo, 40, says by phone from Wheaton, Ill., where he is a music professor at Wheaton College. “War, as complicated as it is, as Americans we have to deal with it — whether you’re antiwar or from a military family.”

When Okpebholo accepted the project, he requested Amaker be tapped to provide the text. The two had collaborated to some acclaim on “Two Black Churches,” a song in two movements commemorating the deadly 1963 bombing at 16th Street Baptist Church in Birmingham, Ala., as well as the 2015 shooting of nine parishioners at Mother Emanuel AME Church in Charleston, S.C. (And, to be sure, one of the most moving pieces of music I heard in 2020.)

Shawn Okpebholo

They’d also collaborated remotely on a reimagined version of “America (My Country ’Tis of Thee),” performed virtually in January as part of the Washington National Opera’s Inauguration Day Concert.

But even with this history of collaboration and that initial experiment in patriotic music, writing for the Tomb of the Unknowns presented a unique challenge.

There’s a heavy irony to the memorial. In one sense, it banishes distraction and demands that we focus our scattered attentions on the sacrifices made across generations of American service members.

At the same time, the potency and power of the Tomb itself as a symbol accommodates an understanding of war that rests in the abstract, remains distant, proceeds unknown. The monolithic presence of the symbol can actually serve to obscure the multiplicity of experiences it stands for.

Okpebholo and Amaker rise to the challenge of commemorating the Tomb by adopting a compositional approach that echoes “Two Black Churches,” not just in the elegant quotation of other pieces (“Taps” and “America the Beautiful” cast passing shadows in “Unknown”) but also in the balance the songs strike between the catastrophe of war and the intimacy of loss.

Amaker’s poetry filters its patriotism through a frank, personal lens — “If death has a sound,” a soldier sings, “then I am now its echo” — and also leaves vast space for Okpebholo’s music to unfurl and say what’s left unsaid.

“I just have always felt like less is more when it comes to the poetry that I do,” says Amaker, 45, from Charleston, S.C., where since 2016 he has been poet laureate. “I really want there to be space for a reader to get it and interpret things, or space for a musician to write music around.”

“The beautiful thing about Marcus’s writing,” says Okpebholo, “is that you think it’s simple, but it’s quite complex. He has this economy of words that’s so evocative and wonderful. As a composer, it’s so natural to set music to his words. It just works beautifully.”

Musically, Okpebholo’s mission was to foreground the solemnity of war, to examine its nature, and to evoke its complex collisions of personal and political scales and stakes.

Sometimes this examination gets specific: The rhythm of the fourth movement — sung from the perspective of the guards — follows a drum cadence of 21/8, inspired by the 21 steps and 21 seconds of rest by which the guards march out their shifts.

“But I also wanted to use my music to create a piece that represents the fact that the Unknowns were many different types of people,” the composer says, noting that the first movement is sung from the perspective of a Black female soldier. “That’s why there’s a soulful section; that’s why there’s a Latin tango; that’s why there are straight operatic moments.”

At Wolf Trap, the premiere doubled as a taping for McIntyre’s forthcoming short film, which mixes footage from the performance with scenes of the singers in character and on location around Washington and the grounds of the cemetery.

“Silence will soon pass through me,” baritone Schyler Vargas sang from the stage. And at the very edge of this line, his voice slowed down and lilted up like a last breath: “and I will remember that I was made to have an ending.”

Okpebholo and Amaker seem to specialize in moments like this, effortless musical updrafts that set the unbearable aflight.

Vargas was joined onstage by another powerful baritone, Michael Mayes, as well as the revelatory mezzo-soprano Taylor Raven, and the singers were accompanied on piano by Wei-Han Wu and by Inscape Chamber Orchestra, conducted by Wood.

The program positioned “Unknown” as its second half, with the companion half comprising a smartly selected suite of six songs bearing heavy echoes from a century ago with uncanny lightness: Irving Berlin’s enduring 1923 standard “What’ll I Do” (sang with steel and softness by Mayes); Charles Ives’s “Tom Sails Away” (1917); H.T. Burleigh’s sublime “I Want To Die While You Love Me” (1919) and “The Sailor’s Wife” (1917); and Oley Speaks’s “When the Boys Come Home” (1915).

The set was tethered to the present by Lee Hoiby’s 2006 “Last Letter Home,” tenderly addressed to a soldier in Iraq.

But after hearing “Unknown,” these old songs — some beloved, some forgotten, all steeped in longing and loss — seem very much of a piece with Okpebholo and Amaker’s project.

There was an openness to those tunes and those narratives that allowed anybody to wander in; yearning was its own uniform, mourning was its own service.

With its idiomatic shifts and open ears, “Unknown” sounds fresh and new and fearless (with a chamber opera and grander plans in the works, Okpebholo is one to watch closely), but it also steps confidently into a rich tradition of American songs that address war in powerfully/helplessly human terms.

This is perhaps best exemplified in the recurring theme of “home.”

The word appears in every movement, echoing itself and reflecting its own meaning to the point of question. “Home” becomes another unknown: Is home a point of departure or a destination? Is home who we are or what we leave behind? And how can we keep it from becoming a war of its own?

Unknown premieres Nov. 11 and will be available as a free stream through Dec. 11 at urbanarias.org/performances/unknown.