Brian Epstein

1934-1967. Manager of The Beatles, catalyst of their change from four leather-clad rockists to four lovable mop-topped pop sensations (with John Lennon and Paul McCartney as latter-day Tin Pan Alley songsmiths-for-hire for a host of
recording artists, including some of the other Liverpool acts Epstein managed) - the silly collarless sportcoats was his idea, IIRC. Various employees and associates, from Derek Taylor to Robert Stigwood to Andrew Loog Oldham, went on to Big Things.

Epstein was almost single-handedly responsible for the Fabs getting on the charts in England. The group was cleverly turned down by every label in the country, but Epstein kept shopping them around.
They were upset with him after Imelda Marcos had them roughed up. Committed suicide while they were in India.

He also managed: Cyrkle, the Bachelors, Cilla Black, Gerry and the Pacemakers, and Billy J. Kramer and the Dakotas.

The Beatles were not in India at the time of Epstein's death; they were in Wales at a retreat run by the Maharishi, only the second time they saw him. They were completely stunned by what happened, and probably became disciples of the Maharishi and later went to his compound in India because the guru offered them a way to cope with the loss of their manager.

It is not really known for sure whether Epstein's death was an accidental drug overdose or an intentional suicide; he had tried to commit suicide before and left notes explaining why, but this time he probably just misjudged the number of sleeping pills to take -- there was no note or anything.

He'd had a difficult life: he was the son of a rich Jewish merchant family in Liverpool, but wasn't very interested in growing up and taking over the family store. He tried being an actor, which didn't last, and after being drafted into the British army, was disciplined for "impersonating an officer" (coming on base in his family car and rich clothes, people saluted him and he didn't correct them) and eventually kicked out when his homosexuality was discovered.

Eventually, he did go into the family business, and was a success in the areas which required current style rather than stolid tradition. He first heard of the Beatles when a guy came into the record part of the store looking for the version of "My Bonnie Lies Over The Ocean" they had recorded as backup for Tony Sheridan. Upon hearing of this popular local band, Epstein checked out their live show and decided he wanted to manage them. (Rumors abound that he had a crush on John Lennon.) He promised the Beatles record deals and all sorts of success, and they signed with him (though Paul's father is known to have had doubts about their having a Jewish manager -- the kind of anti-Semitism that made Epstein rather paranoid throughout his career). Epstein's family wasn't happy that he was going to throw away his work for the store and manage a beat group, either.

He wasn't the greatest businessman, not knowing how to bargain for the best deal, but his manipulation of their image paid off and both they and he became very successful. He wasn't always happy even then, though; he was worried about anti-Semitism, that the Beatles were going to become dissatisfied with him (they were always most important to him of all the bands he managed), and that his homosexuality would become public knowledge (which it really didn't until some time after his death, in Beatles biographies which say that he and Lennon had an affair). He did a lot of drugs to escape his worries, and eventually that probably killed him.

Interestingly, though brutally, Brian Epstein suffered the same fate as Alan Turing, arguably the most brilliant computer scientist of this century (with John Von Neumann being the most notable alternative).

You see, both Brian Epstein and Alan Turing were both homosexuals in England, a country in which homosexuality is not just labeled a mental disorder but also a crime. They were both discovered ("outed," in the worst possible way) and both faced with the humiliating choice between feminizing estrogen treatments or criminal incarceration. They both (as far as we can tell) opted for the relatively less humiliating course of suicide.

Ain't it a bitch when the forces of social opprobrium destroy our best and brightest?

Chaosmind's writeup is simply wrong. Brian Epstein was not outed - and at the time relaxation of laws on gay sex was accepted as a given after the Woolfenden Report. While he was kicked out of the army for his homosexuality, and also blackmailed (the case went to court successfully for Epstein) there was no question of any criminal action being taken against him at the time of his death.
And homosexuality has not been a crime in England since the late 60s - it was actually legalised in the UK before it was in the US - and homosexuality is no longer considered a mental disorder, and hasn't been for decades.