The chant started long before the band took the stage.

“HU!! HU!! HU!!,” yelled the crowd, at escalating volume, for a full 20 minutes before the Hu kicked off their recent concert at the Brooklyn venue, Warsaw. The fans who packed the place, many of whom were decked out in de rigueur heavy metal gear of black T-shirts and leather, thrust their fists into the air in rhythm to their chants, which grew to a roar the moment the band appeared.

The imposing-looking members of the Hu sported leather too, only theirs bore the elaborate patterns and symbols of their homeland, Mongolia. And instead of singing in English, they sang exclusively in their native tongue, delivered in the ancient art of khoomei, or throat singing. In the same vein, their instruments mixed the slashing electric guitars and pounding drums of the west with the richness of the morin khuur (a two-stringed, horse-head fiddle), the tinniness of the tuvshuur (a Mongolian guitar) and the quaver of the tumor khuur (a jaw harp). The beat they kept didn’t so much punch, a la western metal, as gallop, a reference to the horses prized by the nomadic tribes of the band’s ancestors. With so bracing a combination of sights and sounds, the Hu have been forging a highly improbable connection between the complexities of traditional Mongolian music and the 10-ton force of western metal. Think: Genghis Khan ransacking Judas Priest.

“Our music is a blend of east and west, old and new,” said Galbadrakh Tsendbaatar, AKA Gala, the band’s lead singer, through a translator. “We’re building on a history and a sound that has been around for thousands of years.”

Never before, however, has that sound had the impact in the west it’s currently enjoying, courtesy of the Hu. Their first two videos, for Wolf Totem, and Yuve Yuve Yu (or How Strange, How Strange) have amassed more than 45m views on YouTube over the last year, while their debut album, The Gereg, opened at No 1 on Billboard’s Top New Artist chart and No 2 on the magazine’s Indie Label chart. Likewise, it hit No 2 on the UK’s Rock & Metal Album chart and No 4 on the Album Downloads list, while in Australia it broke the top five in overall digital sales. The Hu’s Facebook page has more than 300,000 followers.

Though the band only formed in 2016, their members have been playing their instruments and practicing the tricky rituals of throat singing for most of their lives. The four core members – who also include Enkush (Enkhsaikhan Batjargal), Jaya (Nyamjantsan Galsanjamts) and Temka (Temuulen Naranbaatar) – received formal training at the Mongolian State Music and Dance Conservatory in their country’s capital city, Ulaanbaatar. There, they absorbed a wide variety of music. “Everything from western classical music to jazz to rock and, of course, a lot of traditional Mongolian music,” said Gala.

Along the way, the musicians enjoyed a steady diet of metal, via Metallica, System of a Down and Rammstein. Such music from the west had been banned during the communist era of Mongolia, which ended in 1992. Though the band members were just children then, they remember the cultural upheaval well. “We had to go through hardship,” said Jaya. “The country fell into a financial crisis. But it was something we had to do and, because of that change, we are all able to play rock music.”

In fact, over the last two and a half decades, a significant contemporary music scene has developed in Ulaanbaatar, fleshed out by lots of local pop groups, (such as boy band Camerton), rock acts (like Altan Urag, whose music was featured in the Netflix series Marco Polo), and hip-hop artists (such as breakout star Mrs M, who will soon record in English). Even so, no one had the notion to translate credible, metallic rock to traditional Mongolian styles before B Dashdondog (AKA Dashka), the producer who formed the Hu. After years of working with local pop and rock groups who simply imitated western sounds, Dashka wanted to forge something fresher. So, he hand-picked the members of the Hu from the Conservatory to fulfill his vision. The band say they didn’t choose their name as a play on the Who’s, but because “hu” is the root word for human being in Mongolian. “We took the name because of the inclusive nature,” Temka said. “It’s not about being Mongolian. It’s about being human.”

At the same time, Mongolian themes dominate the band’s lyrics. Many salute their ancestors. “As Mongolians, we are raised to have a great respect for our elders and our history,” said Jaya. “We didn’t come here by ourselves. There are generations of people who paved the way.”

The Hu. Photograph: E.Altankhuyag

Important, too, in the band’s lyrics is a sensitivity to nature. “Human beings and nature are connected,” said Jaya. “And, as nomadic people, we have cattle and we have to move all around so we don’t destroy the land. We respect it.”

As Jaya explained, there’s an essential connection between nature and the intent of throat singing. “What we’re trying to do is imitate the sound of the water, and the sound of the wind,” he said. “Nature is right in our voices.”

While all the members long ago mastered the art of throat singing, it remains a difficult skill to learn. With khoomei, a single vocalist can produce two, or even three, notes at once by forcing air through a tightened throat. The guttural sound that the technique produces can remind western listeners of the dark cries of thrash singers. “Both put a lot of force on your throat,” said Jaya. “It creates a very energetic sound.”

The band’s video for Yuve Yuve Yu likewise stresses the connection between modernity and tradition. It opens with various band members in contemporary settings – an upscale coffee shop in Ulaanbaatar, or at home playing a video game – before Gala opens the door of his urban apartment to enter a vast expanse of mountains and lakes in Mongolia’s remote western region. The images that occupy the rest of the video are so stunning, they could double as a travelogue for the Mongolian tourist board. The band’s second video, for Wolf Totem, unites traditional Mongolian horse riders with leather-clad men on Harleys, suggesting an eastern take on Easy Rider. That connection underscores a bad-ass image that has made the band a natural for metal heads. The smash success of their two videos inspired a rash of labels to woo the band before they even completed their first album. They settled on Eleven Seven Music, home of metal acts from Mötley Crüe to Five Finger Death Punch.

“It wasn’t the amount of views of their videos that attracted us,” said Steve Kline, chief operating officer of Eleven Seven. “It was the fact that their sound is completely unique. We couldn’t even put a label on what they do. We just found ourselves saying, ‘we’re not exactly sure what this is. But it’s really good.”

The Hu’s debut, which the label released last month, took its name from something the Mongol Empire introduced to the world, the first diplomatic passport, which dates from the 1200s. “People think of the Mongol Empire as just warlords and warriors,” said Jaya. “But there are so many positive things the empire brought to the world, like the first postal system, the first international trading on the Silk Road and the diplomatic pass.”

The Hu’s music has become its own passport. Their current American tour has sold out more than half of its dates, and they’ll take their show to Europe at the end of the year and the UK at the start of 2020. For the live dates, they add four auxiliary members to the core foursome, making their sound even more forceful. For another lure, Eleven Seven has begun marketing remixes of their songs featuring cameos from a rash of American rockers, singing in English. The first, for Yuve Yuve Yu, boasts a guest vocal from Danny Case of the rock band From Ashes to New. All the exposure has even helped the Hu attract kudos from some big-name stars. “The other day, Elton John told me he’s a big fan of ours,” Gala said. “He told us it’s been many years since he has heard something this fresh in music.”

That’s good news for rock itself, given the fact that the genre is now often considered an old sound that’s past its peak. “We love rock,” Gala insisted. “But people have never heard it sound like this before. That’s why it’s connecting. It’s something new.”