Joe McDonald, famously known as “Country Joe,” who delivered an impromptu performance of “I Feel Like I’m Fixin’ To Die Rag” at the iconic 1969 Woodstock Festival, has passed away. His rendition became a stirring anthem for the Vietnam antiwar movement.

McDonald was 84 years old at the time of his passing.

The musician from Berkeley, California, died on Saturday due to complications related to Parkinson’s disease, as confirmed by his wife of 43 years, Kathy McDonald, according to a report by the San Francisco Chronicle.

The frontman for Country Joe and the Fish was already well known on the Bay Area counterculture circuit when he took the stage at the famed August 1969 Woodstock Festival for an impromptu solo performance at the urging of the band Santana, which was running a few minutes late and didn’t want to leave the crowd hanging, McDonald recounted in a 2017 interview.

A few songs in, with no one paying attention as far as he could tell, McDonald threw out the first letter in his notoriously profane “Fish Cheer,” which started, “Gimme an F!” and ended with a K. To McDonald’s surprise, he said, the 400,000-strong crowd responded letter for letter, after which he belted out his satirical antiwar song, the famous “fixin-to-die,” igniting the masses.

Born on January 1, 1942, in Washington, D.C., McDonald was the son of Communist parents who initially named him after Joseph Stalin but later abandoned the ideology. His early life was spent in El Monte, California, and he later served three years stationed in Japan with the U.S. Navy before settling back in Berkeley.

In 1965, McDonald co-founded the band Country Joe & The Fish alongside Barry ‘The Fish’ Melton. The band released the single “I Feel Like I’m Fixin’ To Die Rag” and went on to produce five albums, beginning with their 1967 debut “Electric Music for the Mind and Body” and concluding with “CJ Fish” in 1970 before the group disbanded. A final album titled “Reunion” was released in 1977.

Following the dissolution of the band, McDonald embarked on a successful solo career, producing numerous albums. He also ventured into acting, appearing in films such as “Gas-s-s-s-s,” “Zachariah,” and “More American Graffiti,” where he portrayed himself alongside Country Joe & The Fish, as well as in the 1993 limited series “Tales of the City.”