The sisters Hélène and Célia Faussart weren’t trying to jump start a musical movement, but as Les Nubians, the siblings are an international Francophone force, delivering lithe vocal harmonies and uplifting messages set to a panoply of grooves, from reggae and hip-hop to drum ‘n’ bass and cool Sadesque R&B.

Since breaking through with their 1998 debut album, Princesses Nubiennes (Higher Octave), the French-Cameroonian sisters have confidently carved out an American niche, introducing U.S. audiences to Afropean soul. They followed up with 2003’s confident One Step Forward, featuring the Grammy-nominated single “Je Veux D’la Musique,” a slinky Gallic riff on the Gamble and Huff anthem “I Love Music” (a big hit for the O’Jays in 1975).

In a market that eyes foreign languages warily – no music with French lyrics had made a stateside impact for some two decades before the emergence of Les Nubians – the success of the sister act is a cultural watershed. As part of a tour celebrating the release of Nu Revolution, the first album of new Les Nubians songs in seven years, the sisters perform on Friday at the 53rd Annual Monterey Jazz Festival, making their MJF debut headlining on the Arena stage.

“I think we opened the door for a certain side of French culture, and what we call Afropean culture,” says Célia Faussart. “Zap Mama, Soul II Soul, Sade, and other people who started before us, they opened the door for us. But we started singing all in French, and to have that success in a different language was very surprising.

“The first album, Princesses Nubiennes, was the answer to something that people were waiting for here,” she continues. “When it’s your first album, it’s difficult to make a theory about why it’s popular. Our music is a great adventure we’re sharing with American audiences.”

Part of Les Nubians allure is the way the group offers a window into France’s creatively roiling music scene. As the destination for musicians hailing from the far corners of France’s former empire and points beyond, Paris boasts an international array of artists unlike anywhere else in the world, and Les Nubians’ urbane sound reflects the hybrid nature of Paris’s popular culture.

“Our band looks a little like the citizens of the world,” Faussart says. “We have a Cameroonian bassist, a Japanese guitar player and French background singers.”

One reason why it’s been so long since Les Nubians released a set of new material is that the sisters turned their last album, 2005’s Echoes: Chapter One, into a showcase for an international gallery of poets (including San Francisco poetry slam veteran Nazelah Jamison). Inspired by a trip to Nubia, an ancient nation now divided between southern Egypt and northern Sudan, the sisters organized contests in several cities to identify spoken word artists to collaborate with, and then recorded their recitation. After artfully weaving the poems into a larger narrative, they set the verses to various beats, creating an evocative sonic Nubian journey linked by four Les Nubians songs.

“Echoes isn’t really a Les Nubians album,” Faussart explains. “It was our first experience as producers, and it was really coming from the amazing artists and poets we met while we were touring. We thought about sharing the spotlight through our travel adventure. We didn’t rush to make a new album because it’s important to do it when you’re ready. You have to carry songs you’ve lived with and record them when you’re ready.”

The new album was largely inspired by the whipsaw of events in France and the U.S., starting with the riots that swept through the suburbs of Paris in the fall of 2005. Highlighting France’s difficulty in addressing the challenges of a multi-ethnic society, the riots saw youths of North African descent burning cars and engaging in running battles with police.

On the optimistic side, the sisters closely watched the 2008 American presidential race, and like many observers in Western Europe, saw Barack Obama’s triumph as a watershed marking greater Western acceptance of people of African heritage. Faussart is also quick to note that their music flows as much from their personal lives, particularly their experiences as parents, as from newspaper headlines.

“I think this album is inspired by life in general, our life in particular,” Faussart says. “But we’ve always been eyes and ears open to the movements of the world. The riots are part of our context, a reflection of frustration and misunderstanding, a non-evolution in society. As a French citizen and artist, you have to position yourself.”

More than entertainers, the Faussart sisters are trend-setting fashionistas and activists who have collaborated widely with the talent-laden Red Hot & Riot project in the fight against HIV/AIDS. They come to activism by birthright, as their father, an Ashkenazi Jew, was born into a proudly leftist family. He escaped the Holocaust when his mother sent him and his brother into hiding in southern France, avoiding deportation to death camps where numerous relatives perished.

Before they were even conscious of it, Hélène and Célia adopted the global perspective of their parents. Hired as an accountant for a trucking corporation in Chad, the huge, largely desert-covered country in north-central Africa, the family relocated when the girls were little and didn’t return to France until they were well into their teens, plunging them into a starkly different world defined by poverty, political unrest and an unforgiving landscape.

“I arrived in this country that’s not mine, this little French girl born in Paris,” Faussart says. “Everything is different. It’s desert. As a kid, you don’t understand poverty. There are people with guns. It’s a totally weird and wild environment. There’s all this freedom. The kids run outside and spend time with nature, ants and camels. It’s all so grandiose and different. You’re in a war, a country exactly in the middle of Africa, so you have to learn geopolitics. My father was from the generation who lived through the Second World War. We have been aware of history. I think that’s really what we develop in our music.”

LES NUBIANS play the Arena/Jimmy Lyons Stage Friday, Sept. 17, at 9:50pm. See schedule, www.montereyjazzfestival.org.