Plastic Ono Band
Lennon and Ono recorded their first single together, titled "Give Peace A Chance", in a Montreal hotel with a roomful of guests, including Tommy Smothers, Allen Ginsberg, Norman Mailer, Timothy Leary, and the local Hare Krishna chapter. The pair were in an auto accident before the single was to debut (be played in public for the first time), and they had to stay in the hospital. Not wanting to cancel the debut, they sent the first version of their "new band" – a set of plastic cases that held the sound equipment – which played in their place. It was a strange kind of debut for a new band, but the song (a protest against the Vietnam War) became a minor hit that year, in England and in the United States.
The second version of the Plastic Ono Band included Ono and Lennon in person, along with musicians Eric Clapton, Klaus Voormann and Alan White. They performed together at a rock concert in Toronto in September 1969, and it was the first time Lennon had played in public with a band other than the Beatles. The show went well, and helped Lennon decide to leave the Beatles, which he had thought about doing for some time. A second single, "Cold Turkey", was recorded with this lineup.
After the Beatles ended, Lennon decided he did not want to have another permanent band, and he and Ono used the Plastic Ono Band name to refer to any musicians who appeared on the records they made together. Even listeners were called a part of the band, especially when the band gave a concert. An advertisement for one of their records included a page from a telephone book, and the words "YOU are the Plastic Ono Band".
Ono and Lennon separated for a time during 1973 and 1974. Lennon still used forms of the band name on the two albums he released during their separation, while Ono's records of the time appeared under her name alone. When they got back together in 1975, Ono became pregnant, and both decided to retire from music to be parents. Their son Sean Lennon was born on October 9, 1975, which was Lennon's 35th birthday.
In 1980, Lennon and Ono decided to restart their music careers, but this time their records appeared under their own names, and the Plastic Ono Band name was retired.