Chieftains bring a taste of Mexico into their new album

Nurturing a tradition is a tricky enterprise, an exercise in evolution with the tried and true. The further one can straddle back to the past and forward to the future, the more invigorating the outcome. As leader of the Chieftains -- the world's most creative purveyors of traditional Irish music for more than 40 years now -- Paddy Moloney is acutely aware of this nurturing process.

Nearly three decades ago, Moloney was working on a project about the U.S. Civil War -- the Irish had been conscripted on both sides -- when he came upon the obscure story of the "San Patricios," a group of Irishmen who fled the potato famine in the mid-19th century, were enlisted in the U.S. Army but wound up fighting against the United States in the Mexican-American War after the United States annexed Texas in 1845.

"My mind started to go back in time, to these people getting off a boat, being given a big rifle and told to go shoot these Catholic Mexicans by a Protestant general," said Moloney, 71, from a hotel room in San Francisco, a stop on the Chieftains tour that will arrive at Orchestra Hall this Sunday.

"It was a dreadful war. Some of these Irish joined the other side and fought five major battles under John Riley as the San Patricios. They hanged 40 or 50 of them after Churubusco, their last stand, a convent in the desert."

Two years ago, after prodding from guitarist Ry Cooder, Moloney finally followed up on his longstanding intention to record a San Patricios-related album. At first he considered an orchestral work. But as he toured the areas where battles were fought, he discovered that, while the San Patricios were regarded as traitors in the United States and Ireland, they were heroes in Mexico, with folk songs about their exploits.

"I heard all this traditional Mexican music, ballads and songs from eight or nine different regions," he said. "I realized I could fit our music into many of these songs and where I didn't find a tune that could fit, I made one up."

The result is "San Patricio," an exquisite fusion of Mexican sons, boleros and norteños and Irish airs, jigs and ballads that is the most ambitious and adventurous Chieftains record since their breakthrough discs of the 1970s. It is at once a tribute to an emotionally complicated cross-cultural moment in history and a stylistic step forward, beyond even the Galician fusion of the Chieftains' "Santiago" in 1996, which paid tribute to the heritage of a Celtic corner of Spain.

The 19 tracks feature a diverse and beguiling collection of guest musicians. Cooder contributes a song ("The Sands of Mexico") while the vocalists include pop star Linda Ronstadt, singing a traditional ranchera from her Mexican heritage; the 91-year-old Chavela Vargas doing the bolero "Luz de Luna"; Moya Brennan of Clannad, the "First Lady of Celtic Music," and the Mexican singer (and University of Minnesota grad) Lila Downs.

There are traditional Mexican bands such as Los Folkloristas and Los Tigres del Norte, a couple of songs featuring Galician bagpiper Carlos Núñez and a couple others played by Banda de Gaitas de Batallon de San Patricio, Mexico's only pipe band, founded in honor of the Irish fighters. Irish actor Liam Neeson narrates the "March to Battle (Across the Rio Grande)," and nearly everyone gets in on the act on the "Finale."

"That is similar to the finisher-upper onstage in your town, which is like a polka where everybody takes a solo in and out and the audience is doing a snake dance," Moloney said excitedly. He also wants to assure longtime Chieftains fans that Ireland will be very much in the house at Orchestra Hall.

"With this new project our audience is going berserk thinking this is a Mexican show, but that's not the case," he said. "Certainly there will be some of that" -- he estimated 35 to 40 minutes of music from "San Patricio" -- "but there's genuine Chieftains Irish music and we'll have our usual dancers and special guests. It will be a quaffing good show."