Revolver (Beatles album) group collective since 1962, and gave them an unprecedented amount of time to prepare for a new album. Writing in "The Beatles Forever", Nicholas Schaffner cites 1966 as the start of the band's "'psychedelic' period" and adds: "That adjective implies not only the influence of certain mind-altering chemicals, but also the freewheeling spectrum of wide-ranging colors that their new music seemed to evoke." Music journalist Carol Clerk describes "Revolver" as having been "decisively informed by acid", following John Lennon and George Harrison's continued experimentation with the drug LSD since the spring of 1965.<ref name="Clerk/Uncut"> Available at Rock's Backpages (subscription required).</ref>
The Beatles' 1966 tour of Germany, Japan and the Philippines their longtime manager, Brian Epstein, and make the decision to end their career as live performers that year. By contrast, the stay in Tokyo established an enduring bond between the Beatles and Japan, where each of the band members visited or performed in the decades following the group's break-up. Brian Epstein, the Beatles' manager, had intended that 1966 would follow the format of the previous two years, in which the Beatles had made a feature film with an accompanying soundtrack album, toured in North America and select countries during the summer months, and then recorded a second album for a