The Beatles' manager Brian Epstein had been suffering from depression and anxiety for some time, a condition exacerbated by his use of drugs - both prescribed and illegal.
His anxiety had heightened following The Beatles decision to stop touring, which left Epstein with less involvement in their careers. Each member was undertaking individual projects in the late summer of 1966, and he had intended to join John Lennon in Spain on the set of How I Won The War.
On this day, however, Epstein was hospitalised in a London clinic. The official given reason was that it was a check-up, although it later transpired that he had overdosed on prescribed drugs. As a result, he was forced to cancel his visit to Spain in order to recuperate.
Although Epstein is known to have made later suicide attempts, it is believed that this overdose was accidental.