Peter Yarrow, one of the founding members of the folk trio Peter, Paul & Mary, has died. He was 86. His publicist confirmed the news to The New York Times on Tuesday, confirming the cause was bladder cancer, which the singer had been battling for four years. He died at his home in Manhattan.

Born in 1938 to Ukrainian Jewish immigrants in New York City, Peter Yarrow grew up a fan of the arts. He attended music camps over the summer and graduated from LaGuardia High School Of Music And Art. He subsequently got a degree in psychology from Cornell University, and in his final year, a cultural elective course — colloquially known on Cornell’s campus as “Romp-n-Stomp” — forced him to sing and play guitar in public for the first time. He loved it.

Yarrow moved back to New York City after graduating college and quickly immersed himself in Greenwich Village’s fruitful folk music scene, where he’d meet fellow singer-songwriters Mary Travers and Noel Paul Stookey. Together, the three of them decided their voices complemented each other well, and their new band Peter, Paul, & Mary was born. They garnered a local following and nabbed a record deal with Warner Brothers, who released their self-titled debut album in 1962. That album featured Peter, Paul, & Mary’s rendition of “If I Had A Hammer,” a song co-written over a decade prior by one of Travers’ previous collaborators, Pete Seeger.

A lot of Peter, Paul, & Mary’s early hits were covers of other folk artists, namely their 1963 single “Blowin’ In The Wind,” written by an up-and-coming Bob Dylan. It shot up the Billboard charts, and on Aug. 28, 1963, they performed it at Martin Luther King Jr.’s historic March On Washington, establishing it as a civil rights anthem. In 1969, they scored their first and only #1 hit with their rendition of John Denver’s “Leaving On A Jet Plane.”

Across their 13 studio albums, Yarrow co-wrote many of Peter, Paul, & Mary’s best-known songs, including “Puff, The Magic Dragon,” “Day Is Done,” “Light One Candle,” and “The Great Mandala.” A longtime activist in both the music world and in politics, he worked at both Newport Folk Festival and Kerrville Folk Festival, and campaigned for 1968 presidential candidate Eugene McCarthy. Throughout the ’80s and ’90s, he received numerous philanthropic accolades, including the Allard K. Lowenstein Award, the Miami Jewish Federation’s Tikkun Olam Award, and the Kate Wolf Memorial Award.

But Yarrow’s otherwise altruistic legacy was marred in 1970, when he was convicted for sexually assaulting a 14-year-old girl and served three months in prison. He admitted to her accusations, saying: “I am deeply sorry. I have hurt myself deeply. I hurt my wife and the people who love me. It was the worst mistake I have ever made.” Infamously, President Jimmy Carter granted Yarrow a pardon on the final full day of his term. Additional women have since accused Yarrow of similar offenses, saying they were also minors at the time. After his pardoning, Yarrow largely avoided mentioning any of those cases.