The movie is based on Ed Gein's crimes. Gein was a very twisted individual. His actions included grave robbing and creating items from human remains. His story was so grotesque that it caught the attention of the filmmakers. They took his story and added their own fictional elements to create the 'Texas Chainsaw Massacre'. In the movie, we see elements like a chainsaw - wielding maniac, which was inspired by the overall horror of Gein's real - life actions.
It's based on the crimes of Ed Gein. He was a serial killer who did things like stealing corpses from graves and making things out of human body parts.
The 'Texas Chainsaw Massacre' is based on the real - life case of Ed Gein. Gein had a very disturbed upbringing which led to his abnormal behavior. He killed people and used their remains in a very sickening way. For example, he made furniture and clothing out of human skin. These real - life horrors were the inspiration for the movie, with the movie creators taking elements of Gein's story and adapting them into a fictional but equally terrifying narrative in the 'Texas Chainsaw Massacre'.