The Reservoir Dogs star has previously shared details about his childhood trauma with fans, but he always chose to keep the identity of his abuser a secret - until now.

In a new interview with The Guardian, Roth touches on his family's troubled history, revealing his dad, journalist Ernie Smith, was always haunted by his past.

"He was an abused kid, my dad, and it was a terrible childhood that he had, and he took that s**t seriously," Roth explained. "He was a damaged soul. I loved him. He was funnier than f**k. He was abused. And I was abused. But I was not abused by him. I was abused by his abuser."

The 55-year-old reveals his family didn't know how to deal with the situation when he was a child, so he channeled the pain and anger from his own traumatic experience into his 1999 directorial debut, The War Zone, about a teenage boy grappling with the knowledge of his father's abuse of his older sister.

Roth continued, "It (Ernie's abuser) was his father. He was a f**king rapist. But nobody had the language. Nobody knew what to do. That's why I made The War Zone."

The actor's candid confession emerges years after he admitted working on The War Zone, which starred Ray Winstone as the abusive dad, allowed him to work through his "demons".

"Things happen to you in your life, but you don't want to consider yourself to be a victim," he shared at the time. "You want to be a survivor and the first thing that helps you do that and helps you get through it is speaking and finding your voice. I'd been wanting to direct a film for years and told my agent to start looking for a script."

"The first one that came through the door was the one for The War Zone," he added. "If you are a survivor of abuse and you get the opportunity to tell a story about that subject, then you can really get in there and tell the truth. It was a fantastic chance for me to exorcise a lot of demons."