Fifteen books and 25 years at the Forth-Worth Star Telegram both as an investigative journalist and the books editor did not prepare Jeff Guinn for researching, reporting and writing the definitive biography Manson: The Life and Times of Charles Manson.

“To this day I still have some nightmares. The things that happened were awful,” Guinn says about recounting the 1969 murders that cemented Manson as a household name in the late ‘60s and still nearly 45 years later.

In the outset of writing Manson, Guinn simply knew he wanted to write about the turmoil, insanity and chaos that characterized the late ‘60s. He was very close to writing a novel on the Weathermen, responsible for a series of high profile bombings in protest of the U.S. government and its unpopular war in Vietnam.

Then he came across Helter Skelter on his bookshelf. This account of those few bloody days in 1969 written by the prosecuting attorney in the Manson trials Vincent Bugliosi and author Curt Gentry was shocking, well-done and down right chilling, but Guinn wanted to tell the whole story. 

“How, in fact, did he get to that point?” Guinn asks. “He didn’t emerge full-blown and the events don’t happen in a vacuum. How did we create this monster?”

He began by checking Manson’s birth records and quickly dispelled the myth that Manson’s mother, Kathleen, was a prostitute. Guinn traveled to McMechan, West Virginia, Kathleen’s home for many years, where he met towns folk well into their seventies that remembered Manson as a boy and tipped Guinn off to the existence of Manson’s previously unknown relatives: his cousin, Jo Ann, and his sister, Nancy.

“All of these things are new,” Guinn says. “Suddenly you are writing about a human being, an evil human being, a manipulative sociopath of a human being, but he is not a cardboard cut-out any more, a caricature.”

Relatives of Charlie went to great lengths not to be found. His mother went so far as to change the dates and location on her tombstone so they would not match any historical records. Once Guinn managed to find the address of Jo Ann and Nancy, he sent each a formal letter explaining his intent, promising to protect their identities and accompanied with samples of his writing to prove his legitimacy.

“I didn’t want to just show up at the door and say, ‘Hi, for almost 45 years, this has been what you’ve been dreading. Now I’m here, tell me everything,’” Guinn says.

He eventually met with Jo Ann, who shed light into the boy Charles Manson, who lived with her parents and her on two occasions. As a first grader, Manson recruited girls to attack the boys he didn’t like, later telling the principal the girls were acting on their own fruition. “Pretty much the same defense he would use in the Tate-LaBianca murders,” Guinn says. “Even as a child he is violent and fascinated by knives and attacks people.”

Nancy, who was a child when the murders occurred, revealed an untold story of their mother. Charlie portrayed his mother as a “teenage prostitute who once tried to sell him for a pitcher of beer.” Nancy depicted a single mother with an incorrigible 10-year-old who refuses to go to school, is often violent, wants everything and accepts no responsibility.

“One of the biggest surprises of all is how Manson’s whole background is completely different than we were led to believe,” Guinn says. “Nobody ever called Charlie on any of it.”

Guinn met and interviewed for the first time in history Patricia Krenwinkel, one of Manson’s minions serving time for the Tate-LaBianca murders. Equipped with only paper and pencil, he documented every detail of the murders that had never before been heard, not even by police.

“I challenge anybody to have heard some of those things and to try write them all down, get them on the laptop and turn out the light and go to sleep,” Guinn says. “I couldn’t do it.”

His most shocking discovery is Manson’s tactics for manipulation. After asking Manson’s longtime cellmate how the man was so convincing, almost able to read people’s minds according to some accounts, the inmate responded, “I have been waiting almost fifty-fucking-years for somebody to ask me that question.”

As part of a prison program, Manson participated in a Dale Carnegie “How to Win Friends and Influence People” course. “Manson lifted Dale Carnegie, adjusted it some with mumbo jumbo he learned on the corners of Haight-Ashbury, mixed it up with fundamentalist religion and Beatles song lyrics and put that out there as a perfect world philosophy and there were people who bought into it,” Guinn says.

“Why are we even talking about Charles Manson?” I ask Guinn. “Are we not lending credence to his violent, sociopathic deeds?”

Most don’t remember the names of the teenagers who committed the school shootings at Columbine and in a matter of years few will remember the names of the Boston bombers, yet nearly half a century later everyone knows the name Charles Manson, he says.

“If for no other reason, Manson remains the icon he is because of the almost mystic sense that he has created about himself,” Guinn says. “Well, this book is the demystification of Charles Manson.”

Ian Floyd is a journalism major at the University of Texas at Austin and the features intern at Kirkus reviews. Follow him on Twitter.