John Renbourn, an English guitarist known for his light-fingered fusion of classical, folk, blues and jazz and for his work with the group the Pentangle, was found dead on Thursday at his home in Hawick, Scotland, near the English border. He was 70.
He had been touring with another guitarist and singer, Wizz Jones, who was one of his earliest influences. When he did not show up for a concert in Glasgow on Wednesday, his agent contacted the police. The cause had not been determined, but a police spokeswoman said there were “no suspicious circumstances.”
Mr. Renbourn was both an antiquarian and an innovator — part of a generation of British and American guitar virtuosos who in the 1950s and ’60s reached deeply into traditions but were not bound by them.
As early as the 1960s, Mr. Renbourn delved with scholarly dedication intomedieval and Renaissance music; his “Complete Anthology of Medieval and Renaissance Music for Guitar.” a sheet-music collection of 28 pieces, was published in 1995. He learned British folk songs and sang them in an amiable tenor, and he was drawn to ragtime and the blues, particularly the fingerpicking complexity of early rural blues.
His music also used the harmonies and phrasing of jazz guitar and an occasional hint of flamenco, and he studied the sitar and the shakuhachi, the Japanese wooden flute.
He was a founder of the Pentangle — which he named after the five-pointed star, symbolizing five virtues, on the shield of Sir Gawain in the medieval Arthurian poem “Sir Gawain and the Green Knight” — in 1968 with the guitarist Bert Jansch, the singer Jacqui McShee, the bassist Danny Thompson and the drummer Terry Cox.
The core of the group was the pairing of Mr. Renbourn and Mr. Jansch, who made their first duo recordings in 1965. They forged a tandem style that became known as “folk-baroque,” full of gnarled harmonies, spiky counterpoint and melodic filigree.
The quintet added Ms. McShee’s soprano — she had sung on Mr. Renbourn’s 1966 album, “Another Monday” — and a jazz-inflected rhythm section to make music that was mostly acoustic (although Mr. Renbourn played some electric lead guitar), intricately arranged and pointedly eclectic. Its repertoire included the group’s new songs, an a cappella medieval dirge, a girl-group remake, Charles Mingus pieces, blues tunes and traditional ballads.
The Pentangle first visited the United States in 1969, appearing at the Newport Folk Festival, at Carnegie Hall and — opening for the Grateful Dead — at the Fillmore West. The original version of the group made its last studio album, “Solomon’s Seal,” in 1972 before touring and then disbanding. The group reunited in the early 1980s, but Mr. Renbourn left before it made any new records.
The original quintet eventually regrouped for the BBC Folk Awards in 2007, and went on tour in 2008. It also played concerts in 2011, its last shows before Mr. Jansch’s death in October 2011.
Mr. Renbourn had a prolific career both before and after the Pentangle years. Born in London on Aug. 8, 1944, he got his start in folk clubs there and made his first album in 1965 with Dorris Henderson, an American singer based in London.
He also recorded extensively on his own and in collaboration with many luminaries of British and American folk music, among them the American folk-blues guitarist Stefan Grossman, with whom he made four studio albums and a live album, and Robin Williamson of the Incredible String Band. Their collaboration (“Wheel of Fortune,” 1994) brought Mr. Renbourn a Grammy nomination.
Mr. Renbourn’s final studio album was “Palermo Snow,” released in 2010.
He had a pedagogic side. In the early 1980s, well into his career, he enrolled in a three-year music course at Darlington College in England, where he would later teach. He published sheet-music anthologies, including a piece from the revered Irish harpist Turlough O’Carolan, and an instruction book, “John Renbourn Fingerstyle Guitar.” He taught guitar at universities in the United States (including Columbia), Canada and Britain, and held guitar workshops across Europe.
His marriages to Jo Watson and Judith Hills ended in divorce. He is survived by three children, Joel, Jessie and Ben.
Mitch Greenhill, who produced three albums by Mr. Renbourn, recalled him in an email: “He was most at home in his practice studio, sheet music on a stand, guitar on his knee, trying to channel the muse that hovered just beyond the temporal world.”