LOS ANGELES — Vincent Bugliosi was an anonymous junior member of the Los Angeles County District Attorney’s Office when he was handed the case that, for better or worse, would define his life: the prosecution of one of America’s most notorious mass murderers, Charles Manson.

During a closely watched and oftentimes bizarre trial that lasted nearly a year, the cool, relentless prosecutor became nearly as famous as Manson himself as he denounced the ersatz hippie cult leader as the “dictatorial maharajah of a tribe of bootlicking slaves.”

He called Manson’s three murderous disciples, who were on trial with him, “robots” and “zombies.” He told jurors they killed actress Sharon Tate and six others during a two-night rampage that terrified Los Angeles in the summer of 1969.

After all were convicted, Bugliosi would go on to recount the case in “Helter Skelter,” one of the best-selling true-crime books of all time.

He would write 11 more books after that, but Bugliosi, who died Saturday at age 80, would always be best remembered as the man who put Manson and his followers away. He reflected on the reasons for that in an interview 40 years after the slayings:

“These murders were probably the most bizarre in the recorded annals of American crime,” he said. “Evil has its lure and Manson has become a metaphor for evil.”

Bugliosi was a young, ambitious deputy district attorney on Aug. 9, 1969, when the bodies of Tate, the beautiful actress and wife of director Roman Polanski, and four others were discovered butchered at a hillside estate.

The victims included members of Hollywood’s glitterati: celebrity hairdresser Jay Sebring, coffee heiress Abigail Folger, Polish film director Voityck Frykowksi and Tate, who was 81/2-months pregnant. Also killed was Steven Parent, a friend of the estate’s caretaker.

A night later, two more mutilated bodies were found across town in another upscale neighborhood. The crime scene was marked with the same bloody scrawlings of words including, “Pigs,” “Rise” and “Helter Skelter.” The victims were grocers Rosemary and Leno LaBianca, who had no connection to Tate and her glamorous friends.

When members of the rag tag Manson Family were caught and charged with the crimes months later, a more veteran prosecutor, Aaron Stovitz, was removed after making an offhand remark to reporters mocking one of the defendants.

Bugliosi took over. The trial went on for so long that a defense lawyer disappeared and was found dead in the woods, something that led to retrials for a co-defendant, Leslie Van Houten, who was convicted again. Bugliosi maintained foul play was involved but that was never proved.

When the trial was over and all were convicted, Bugliosi wrote, “Helter Skelter.”

Later he was defeated in bids for Los Angeles County district attorney and California attorney general. He tried his hand as a defense attorney but said never felt comfortable in that role.

Born in Hibbing, Minnesota, in 1934, Bugliosi attended the University of Miami in Florida on a tennis scholarship. He earned a law degree from UCLA. He and his wife of 59 years, Gail, had two children, Wendy and Vincent Jr.