"Woodstock" is a song written by Canadian-American singer-songwriter Joni Mitchell. At least four notable versions of the song were released in the same year, 1970. Mitchell's own version was first performed live in 1969 and appeared in April 1970 on her album Ladies of the Canyon and as the B-side to her single "Big Yellow Taxi". This publication was preceded by Crosby, Stills, Nash & Young's version, which appeared on their March 1970 album Déjà Vu and became a staple of classic rock radio and the best-known version in the United States. A third version, by the British band Matthews Southern Comfort became the best known version in the United Kingdom, and was the highest charting version of the song, reaching the top of the UK Singles Chart in 1970. A fourth version by studio project the Assembled Multitude also became a chart hit.

Roberta Joan "Joni" Mitchell is a Canadian-American singer-songwriter, multi-instrumentalist, and painter. As one of the most influential singer-songwriters to emerge from the 1960s folk music circuit, Mitchell became known for her personal lyrics and unconventional compositions which grew to incorporate pop and jazz elements. She has received many accolades, including eleven Grammy Awards and induction into the Rock and Roll Hall of Fame in 1997. Rolling Stone called her "one of the greatest songwriters ever", and AllMusic has stated, "Joni Mitchell may stand as the most important and influential female recording artist of the late 20th century."