Whenever a body of travelers—whether soldiers, refugees, missionaries, slaves, adventurers, or any other kind of group—moves across a wide geographical distance and encounters a very different group somewhere else in the world, there is inevitably interchange of cultural ideas, which almost certainly also include music. Spain’s Golden Age in the 16^th century involved travel and conquest over an enormous geographical area in Central and South America. Soldiers were followed by priests and missionaries, and slaves were carried along as well. All of them not only brought their own music to the New World, but also heard and absorbed native traditions already present there.

These complex and blended traditions have lasted for centuries, with further development of course, but retaining the sense of their being essentially Hispanic in character. Celebrating this tradition, with centuries-old tunes from both the Old World and the New, the distinguished performer on the viola da gamba Jordi Savall brought Hesperion XX to Tanglewood last week, with a Mexican contemporary ensemble the Tembembe Ensaemble Continuo for a wide range of these traditional melodies in traditional and modern versions.

At Ozawa Hall last Thursday, Hesperion XX consisted of three players: Savall himself, playing the viola da gamba and the treble viol; David Mayoral, percussion; and Xavier Díaz-Latorre, theorbo and guitar. The Mexican ensemble likewise comprised three: Ulises Martínez, violin, guitarra de son, and voice; Enrique Barona, gitarra huapanguera, leona, jarana jarocha 3a, mosquito, maracas, pandero, and voice; and Leopoldo Novoa, marimbol, guitarra de son 3a, jarana huasteca, quijada de caballo, and arpallanera. It may be clear from this list that f Hesperion XX chooses historical instruments of the Renaissance while the Mexican musicians play instruments largely from a folkloric heritage.

Each half came in four segments, partly presenting the older music from the 16^th century and its echoes from the 17^th and early 18^th centuries, and partly involving modern improvisation on traditional tunes. Most of these traditional tunes have a Spanish origin, although there were surprises including an improvisation on the ground or bass pattern of the English song “Greensleeves,” or one group of Celtic traditions in the New World—some traditional Scottish melodies, including one from a collection printed in Boston in 1883. Despite its late date, that collection, containing 1050 dance tunes, summarizes more than a century’s collection of popular tunes carried widely over the New World.

But most of the music was derived from tunes based on well-known patterns of the Renaissance, the folia, the passamezzo antico, the passamezzo moderno, the romanesca, and the ruggiero. These form to the basis of a large repertory of Renaissance and Baroque performance practice, usually involving improvisations over the bass line. The best-known of these, without doubt, is the folia, which had a busy afterlife well into the 18^th century, especially in Italy.

Many of the variations performed by Jordi Savall come from a collection called Trattado de glosas (Treatise on ornamentation) by Diego Ortiz, published in Rome in 1553. In general, these begin with simple examples filling in gaps in the scale and developing faster and faster subdivisions of the notes until they become spectacularly virtuosic. This is of course the long-established specialty of Jordi Savall, whose extraordinary fingering and bowing became quite breathtaking by the ends of pieces.

But there were also other types of works including music ostensibly from the Moorish tradition (Moresca), with a strong Arabic flavor in its 5/2 rhythm. Throughout the program the six performers interacted flexibly sometimes in solos for a time or duets or larger ensembles. Each half of the program built to a particularly stunning and energetic number largely improvised, and filled with the personality of the dance, such as to make it hard to keep one’s seat.

When the audience at the end seemed to refuse to let the performers go, they returned to the stage for one more lengthy, brilliant, rousing fandango to send everyone home in high spirits.

Steven Ledbetter is a free-lance writer and lecturer on music. He got his BA from Pomona College and PhD from NYU in Musicology. He taught at Dartmouth College in the 1970s, then became program annotator at the Boston Symphony Orchestra from 1979 to 1997.