The trio Kneecap is pioneering Irish-language rap, a genre that barely existed a decade ago.BELFAST, Northern Ireland — On a recent evening in a small, rowdy, West Belfast bar, Mo Chara and Móglaí Bap, two members of the rap group Kneecap, were posing for photographs with fans. One of the bar’s patrons, tapping out a text message nearby, called out to the rappers, “How do you spell ‘ceart go leor’?” an Irish phrase meaning something like “OK.”It might seem like a weird question for hip-hop artists, but Kneecap’s members should know. They have found fame here in a genre they are pioneering: Irish-language rap.Since 2017, when Kneecap released “CEARTA” (the Irish word for “rights”), the band’s popularity has been growing on both sides of Ireland’s internal border and among the diaspora across the Irish Sea. The band’s signature blend of ramshackle rave and rudimentary hip-hop beats, mixed with republican politics — in the Irish sense of seeking unity for the island’s north and south — has brought Kneecap sold-out gigs in Belfast and Dublin, and a growing fan base in England and Scotland.Even a decade ago, the notion of Irish-language rap seemed fantastical. But something is happening in Ireland — north and south — which lately finds itself in the midst of a so-called Celtic revival, with questions of identity, place and culture being interrogated across the arts, politics, fashion and even spirituality.The Irish language is central to this resurgence. The dominance of English in Ireland is a legacy of British colonization, stretching to the 12th century. English became the language of opportunity, progress and employment, and Irish came to be seen as incompatible with modern life. But people carried on speaking Irish in some pockets of the island, and a boom in Irish-language schools from the 1970s raised new generations that viewed the language with pride and enthusiasm rather than shame and resistance.D.J. Próvaí showing a photo of his father’s arrest during the Bloody Sunday uprising of 1972.Paulo Nunes dos Santos for The New York TimesRepublican murals in the Falls Road district of Belfast.Paulo Nunes dos Santos for The New York TimesKneecap’s signature style blends ramshackle rave and rudimentary hip-hop beats with republican politics.Paulo Nunes dos Santos for The New York TimesKneecap was born out of an Irish-speaking west Belfast squat, whose all-night parties featured both techno and traditional Irish music on the sound system. “We felt there was something bubbling, and we wanted to represent that,” Móglaí Bap said.“Irish language and culture doesn’t necessarily have to be an image of rural traditional music,” Mo Chara said. “It can involve youth culture.”Kneecap’s lyrics feature republican slang and slogans — often used in a tongue-in-cheek manner — that have stirred controversy in Northern Ireland. D.J. Próvaí, the third band member, said he left a job as an Irish teacher in 2020 after his school objected to a Kneecap video in which an anti-British slogan — “Brits out” — appears drawn on his buttocks.“Republicanism is so vast, and on a spectrum,” Móglaí Bap said in an interview. “We like to toy with it. We like to take the irony on, and also not be dictated about what kind of republicanism we’re going to believe in.”Frequent references to taking drugs in the band’s lyrics have placed Kneecap at odds with republican dissidents, many of whom have a zero-tolerance policy toward drug use. (The band’s name comes from a form of torture that republican paramilitary groups would inflict on those they accused of drug dealing.) “We’re screaming about the ‘Ra,” Móglaí Bap said, using a familiar name for the Irish Republican Army, “even though the ‘Ra would probably shoot us for doing all of these sort of things.”Not all artists embracing the Irish language are motivated by politics, however: Often, it is as much about rediscovering the past as reckoning with the present. In summer 2020, Manchán Magan, a writer and broadcaster, published “32 Words for Field,” a catalog of lost words to describe the Irish landscape. The book recalled ancient Irish terms like “scim,” which can mean a thin coating of particles, like dust on a shelf, “but it can also mean a fairy film that covers the land, or a magical vision, or succumbing to the supernatural world through sleep,” Magan writes.“32 Words for Field” was an instant cult hit, and it became a mainstream one. Its initial print run sold out in pre-orders before it reached bookstores.Magan said the recent boom in Irish-language creativity was part of a continuing search for an Irish identity, unshackled from colonialism and Catholicism. “What we’re trying to do is rooting ourselves back to — not nationalism, but those things that came before the nation,” he said in an interview. “Connection with the spirit, or some sort of universal mythology, all of those things that bring us together, that make us realize we’re united.”Catherine Clinch, left, and Carrie Crowley in a scene from “The Quiet Girl,” an Irish-language movie that won two honors at this year’s Berlin International Film Festival. InscéalIn Irish-language cinema, barely a genre a few years ago, the latest hit is “The Quiet Girl” (“An Cailín Ciúin”), which last month won two honors at the Berlin International Film Festival, and this month beat the Academy Award-nominated “Belfast” to win best film at the Irish Film and Television Academy Awards. Adapted from a 2010 short story in The New Yorker by Claire Keegan, “The Quiet Girl” was partly funded by an initiative called Cine4, run by the Irish-language television station, TG4.The film’s writer-director, Colm Bairéad, said he looked forward to the film being screened around Europe, when audiences would hear “the Irish language bouncing around these auditoriums where the language just hasn’t been heard throughout the history of the medium.”Cleona Ní Chrualaoí, the producer of “The Quiet Girl,” said the current resurgence of Irish-language creativity was, in part, because of people who went through the Irish-language school system. “That has really helped our positive relationship with the language,” she said. “We have generations of children, who have become adults who really respect the language.”Móglaí Bap said Kneecap’s members came from “probably the first generation coming out of the Irish-language education system that developed their own sense of identity within the language.” For the band, rapping in Irish wasn’t just about lyricism, or even identity, Mo Chara said. It offered, he added, “a completely different understanding of the culture, and even of reality around you.”“We found this wee niche,” Móglaí Bap said. “The language is a way for us to bring people with us.”Kneecap has played sold-out gigs in Belfast and Dublin, and has a growing fan base in England and Scotland.Paulo Nunes dos Santos for The New York Times More