1971 would be a very creative year for John. Early in the year he released the protest single "Power To The People'', which was yet another hit. He would move to New York City that year and work on his next album. Imagine was released in October and went to number one internationally. The title cut would become the most loved song by his fans and his most remembered. A paean for peace in a world with no Gods or personal possessions, where everyone is equal. But the album also contained a few portent protest songs, including "How Do You Sleep?" which was a direct attack on Paul McCartney. In December he released the Christmas anti war single "Happy Christmas (War Is Over)".

More political songs would show up on his next release in 1972, Sometime In New York City, a double album. By this time he also was in a legal battle with the US government. He wanted to stay in the country but US Immigration refused to give him a green card due to a conviction for marijuana possession in 1968. In 1973, he was ordered to leave America, and he launched a full-scale battle against the department. At the end of that year, he released the album Mind Games, an album that highlighted problems between him and Yoko. In early '74 he and Yoko split up and John moved to Los Angeles where his "Lost Weekend" would take place for the next year and a half. He spend most of it in a haze of drugs and alcohol partying hard with several different rockers including Harry Nilsson, Keith Moon and Ringo Starr. During this time not all was lost, as he produced Nilsson's album Pussycats. He also recorded and released in November a new studio album, Walls And Bridges. The album contained the single 'Whatever Gets You Through The Night", a powerful rocker written with Elton John, which went to number 1 in the US. That month, he made his last ever concert appearance when he appeared onstage at Madison Square Garden with Elton John. That night John was reunited with Yoko and they would get back together for good.

In 1975, his cover album of 50s and early 60s hits was released. Rock 'N' Roll went to number six on both the US and British charts. But even better news awaited him. That October, after the birth of his and Yoko's son Sean, the US court of appeals overturned his deportation order. In the summer of 1976, he was finally granted his green card. Also around that time, he co-wrote and appeared on David Bowie's hit single "Fame". He then decided to retire from music, choosing to become a house husband, while Yoko looked after their business interests.

In 1980, John returned to recording, signing a new contract with Geffen Records. He released with Yoko, the album Double Fantasy that November, which went to number 1 worldwide. The album's first single, "(Just Like) Starting Over," was also a big hit. Then on December 8, 1980, while returning from the recording studio, he was assassinated by a gunman (name purposely withheld in honor of John's families' wishes) outside his apartment building in Manhattan. His death drew grief from the entire world; as everyone reacted in unprecedented mourning, with scenes usually reserved for world leaders. On December 14, millions of fans around the world participated in a ten-minute silent vigil for him at 2 p.m. EST. The dream that Lennon had sang about years earlier was now truly and sadly over.

Several albums of his unreleased recordings would show up in the years after his death. But his song writing with Paul McCartney would go down as rock's best writing team ever; the Beatles rock's most loved group, and his life both in and out of the Beatles perhaps rock's most interesting. There will never be another like John Lennon.