There was a massicure somewhere in Vietnam.
No, it's a pure work of fiction. Despite the disclaimer at the beginning of the movie that it's based on a real story, this is itself a fiction, designed to make it look like it's a drama-documentary and probably used as a ploy to get more people to go and see the film.The movie, along with Psycho which was released in 1960, was based upon the case of Winsconsin farmer Ed Gein, a psychotic maniac who was convicted of murdering two women in 1954 and '57, was suspected of killing three more whose remains were never found, and who exhumed the bodies of other people from local graveyards in order to make clothing and keepsakes from their bones and skin- one such was his own mother Augusta. He ate some of his victim's body parts, kept their bones and other remains around his house, and kept their disembowelled torso's hanging in one of his outhouses. But he didn't use a chainsaw to kill them, he shot them instead with a .22 calibre rifle. Gein died in a Madison mental hospital in July 1984 aged 77, of a heart attack brought on by cancer.But no 'Texas Chainsaw Massacre' ever happened in real life.