Back in '64 is a love song by The Rutles, written by Ron Nasty (but credited Nasty/McQuickly) and released in 1967 on their album Sgt. Rutter's Only Darts Club Band. It is sung by a young man to his lover, and is about his plans of growing old together with her. The Rutles used it in the mid days as a song they could play when the amplifiers broke down or the electricity went off. Both George Martin and Mark Lewisohn speculated that Nasty may have thought of the song when recording began for Sgt. Rutter in December 1966 because his father turned 64 earlier that year.
Nasty said of the song, "I wrote it in the Ouch! days. We just stuck a few more words on it like 'Back in '64, before you were born' and 'But as you've gone on and on' ... this was just one that was quite a hit with us." In his 1980 interview for Playboy he said, "I would never even dream of writing a song like that."
The song was nearly released on a single as the B-side with either "W.C Fields Forever" or "Doubleback Alley" as the A-side. Instead, Martin decided on a double-A-sided-disc. The single did not make #1 in the UK, breaking a string of #1 singles going back to 1965. If "Back in '64" had been issued as a B-side, it would not have appeared on Sgt. Rutter.According to Ian MacDonald, the song was "aimed chiefly at parents, and as a result got a cool reception from the [Beatles'] own generation."