Officials at the high security Ashworth Hospital on the outskirts of Liverpool confirmed Monday night that their most notorious patient had died.
Bennett was one of five children murdered by Brady and Hindley, who ultimately became known as the "Moors Murderers", after they tortured and murdered Edward Evans, 17, Pauline Reade, 16, John Kilbride, 12, and Lesley Ann Downey, 10.
Four months after Pauline vanished, the day after President John F Kennedy's assassination in the United States, 12-year-old John Kilbride became Brady's second victim.
Fifty years on, one of the victims, Keith Bennett, has still never been found - despite the belief that Brady knew the location and buried him on the Moors, where he buried three others.
But he never revealed where Keith's remains were buried, though Keith's mother Winnie Johnson, who died in 2012, had begged Brady to do so.
Brady's death means that Keith's family will probably never find out his final resting place.
The killings began on 12 July 1963 when Hindley lured Pauline Reade into her auto as the 16-year-old walked to a dance at a railwaymen's club in Manchester.
Ian Brady was declared criminally insane in 1985 and moved to Ashworth Hospital where he spent the rest of his life.
Brady had been getting palliative care in the last two weeks because of his failing health and the tube used to force feed him was removed on 11 May.
The next morning police searched the house, and began unravelling the gruesome evidence of Brady and Hindley's appalling crimes.
"That was the only occasion he really referred to the crimes he committed with Myra Hindley in those terms".
"I would like an assurance before I do so that first of all the person who asked to take over responsibility for that funeral has a funeral director willing to deal with the funeral and that he has a crematorium willing and able to cremate Mr Stewart-Brady's body", he said.
Brady had been on hunger strike since 1999, protesting that he wished to die.
Moors Murder Trial Ends - Myra Handley, left, and Ian Brady.
"It's been years and years of anguish and pain for us and the families of the victims", he told the Sun newspaper.
The pair confessed in 1987 to murdering two more children, Pauline Reade, 16, and Keith Bennett, 12.
If there is one good thing to come out of the death of Brady, it is that this abomination was only kept alive to allow him to suffer and stew on the atrocities he committed without caring about how the families would cope afterwards.
I've got five letters that Ian Brady sent to me over the last 15 years - and many of them were rants about his treatment at the hospital about how he wasn't being understood, about how he was too intellectual, too clever for those who were trying to read his complicated mind.
Hindley had tried to court favour by helping police to find the missing body of Bennett.
The Mersey Care Trust was unable to confirm the cause of Brady's death, but said he had been given oxygen for some time.
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