Charles Manson, the ’60s cult leader behind one of the most notorious killings in American history, died Sunday in California after a prolonged illness, officials said. He was 83.

Manson – housed at Corcoran State Prison since 1989 – died at 8:13 p.m. local time at Kern County Hospital, the California Department of Corrections said in a press release early Monday.

He’d been in failing health for months and was first hospitalized back in January, reportedly with serious gastrointestinal problems.

Manson — who infamously wore a swastika tattoo between his eyebrows — had spent more than 45 years in prison after being convicted of directing his “Manson Family” clan of troubled, mostly female, followers to kill seven people in California in the summer of 1969. The dead included actress Sharon Tate, the pregnant wife of director Roman Polanski, who was stabbed 16 times.

“I am crime,” Manson proudly proclaimed during a collect call to The Post from prison in the mid-2000s.

Born on Nov. 12, 1934, in Cincinnati, Ohio, to a prostitute named Kathleen Maddox, Manson was officially dubbed “no name Maddox” at birth and apparently never knew his biological father.

From a very young age, Manson was a self-styled “outlaw” who took pride in being a criminal and reveled in all the mayhem he caused.

Manson committed his first crimes at around 13 years old, robbing liquor stores to scrounge together enough money to eat and rent motel rooms.

During his teenage years, Manson was in-and-out of juvenile halls and was placed in the Indiana Boys School, where he was sexually assaulted before he escaped in 1951, according to a book, “Manson In His Words,” by Nuel Emmons.

Between 1951 and 1955, Manson was repeatedly arrested for a variety of federal and state offenses, including stealing cars and robbing gas stations.

He was sent to reformatories, but none of them could wean him off his appetite for trouble.

By 1957, Manson was doing hard time in the federal prison at Terminal Island in Los Angeles for violating his probation after he was caught stealing a car and driving it over state lines.

He was eventually paroled, but started a career as a pimp and tried to cash forged US Treasury checks.

Manson found himself back at Terminal Island, where, on March 21, 1967 – the day of his release – he pleaded with prison officials to keep him there because he had been institutionalized for most of his life up to that point.

The wild-eyed, gnome-like figure ended up staying in Los Angeles, where he wrote and played music with a guitar – and began a hippie cult that drew tough men and disaffected suburban young women.

But Manson’s inability to build a musical career led him to an even darker path.

Manson hung out with Beach Boys drummer Dennis Wilson and the band’s record producer, Terry Melcher, but the latter refused to give him a record deal.

Furious, Manson put together a plan to exact his revenge, ordering several of his drug-addled, brainwashed followers to kill everyone inside Melcher’s former residence.

Despite knowing that Melcher no longer lived there, Manson specifically chose that location because it represented the music industry that had snubbed him.

Just as importantly, Manson, who harbored bizarre racist theories and philosophies, wanted to start a race war – something he called “Helter Skelter,” named after the Beatles song by the same name.

On Aug. 9, 1969, Manson’s disciples, Charles “Tex” Watson, Susan Atkins and Patricia Krenwinkel, descended on Melcher’s former compound in Benedict Canyon, where pregnant actress Sharon Tate was now living with filmmaker Roman Polanski.

Polanski was overseas shooting a movie at the time, but Tate was hosting a low-key party with friends, including hair stylist Jay Sebring, coffee heiress Abigail Folger and her boyfriend, Wojciech Frykowski.

First, the killers fatally shot Steven Parent, who had been visiting a caretaker on the property. They then butchered to death Tate, Sebring, Folger and Frykowski.

The next night, Manson directed Watson, Krenwinkel, Atkins and another follower, Leslie Van Houten, to murder supermarket magnate Leno LaBianca and his wife, Rosemary LaBianca, in their Los Feliz home.

In the decades since the murders, Manson has become an icon for troubled youth and a fixture in pop culture.

There have been numerous books written about the “Manson Murders,” as well as movies and documentaries detailing the case.

Manson himself reached almost mythical status through his strange and colorful prison interviews with notable media types, including Charlie Rose, Diane Sawyer and Geraldo Rivera.

In his final years in prison, Manson almost married Afton “Star” Burton, who moved from Mississippi to Corcoran just to be with him.

Although they filed for a marriage license, Manson never got hitched to the woman who is more than 50 years his junior.

No one who carried out murders at Manson’s behest has has ever been released from prison.

Watson, Krenwinkel, and Van Houten remained locked up in California while Atkins died in prison in 1989.

A board granted Van Houten – who at 19 was the youngest of the killers – parole in September.

But the ruling is still under review and California Gov. Jerry Brown will get to uphold, reject or modify the finding of parole early next year.

Additional reporting by David K. Li