Natalie Portman never really considered making her new film, “A Tale of Love and Darkness,” in anything besides the Hebrew language.

Calling recently to discuss the movie (opening Friday), which she wrote and directed as well as playing the lead — the Academy Award winner admitted, “I certainly had suggestions from people to make it in English, but I really felt that I would lose a lot of authenticity from the film if I didn’t make it in Hebrew.” An added factor had to do with the central themes of the book upon which the movie is based.

The film, Portman’s debut as a feature director, is the big-screen interpretation of acclaimed Israeli author Amos Oz’s very personal memoir of the same name. Therefore, for Portman, doing the movie in Hebrew was “as central to the story because everyone in it is so obsessed with language and words and writing.”

Oz’s book largely focuses on the late 1940s and the founding of the state of Israel in 1948, creating a practical issue as well. “Hebrew, the language, itself was revived at this time,” Portman said. “It was a biblical language that hadn’t been spoken in hundreds of years. It had only been used in a religious context — like Latin — and then all of a sudden they decided to use it in everyday conversation.

“Things like, ‘Can you fill up my car with gas,’ now had to be worked into daily life — and in Hebrew, the official language of the new Israel. They had to figure out all these new words to create ways for modern communication,” said Portman.

While the actress came to the United States as a young girl, she was born in Jerusalem and obviously accepts that as her heritage. “It definitely is a strange feeling to have as your first language and the marker of your earliest emotions to be something that is transcribed deep inside you. Yet, it also is interesting that this language to which you feel the most emotional is not the one that is your dominant language — since, in my case, that is English.

“It’s intriguing that this original language is not the language I’m most comfortable in. My vocabulary isn’t great. My accent isn’t great. Yet, it is the language of my childhood and the language of my heritage. Making this film was a lucky opportunity for me to go back and visit and relearn my first language.”

The film focuses on the close relationship between Amos Oz and his mother, Fania — who Portman portrays in the film. A deeply sensitive woman who battled depression and frequently harbored suicidal thoughts, Fania escaped her unhappiness in her marriage by weaving fantastical stories for her beloved son, Amos — imbuing him with a love of poetry, language and storytelling and laying the groundwork for him to become arguably the greatest living Israeli writer.

Getting to know Oz so well is something Portman called “one of the greatest things that has happened to me in my life.” Yet, besides the passion to share Oz’s early life in “A Tale of Love and Darkness,” Portman also said that from the moment she read Oz’s memoir, “I felt the film it could become right in front of my eyes. That is a testament to Amos’ writing first and foremost. After all, the relationship he described between the mother and son really moved me.

“Yet beyond that, the time period here — the late 1940s — has figured so deeply in my imagination since I was a child. I so clearly remember hearing the stories of what it was like when my grandparents came from Eastern Europe and came to what was then British Palestine. I had it in my imagination for so long. I think that’s often what people make for their first films. For some, their childhood imagination is about outer space. For others it’s about fast cars, or whatever. In my case, my childhood imagination was about this.”

Among what Portman called “the many, many gifts” Amos Oz gave her was his strong encouragement to do her own thing as far as filming his memoir.

“As he told me, ‘The book already exists. Don’t just film the book. Try to make your own piece,’ ” added the actress and filmmaker, who noted Oz shared family photo albums and actually took her to his old Jerusalem neighborhood so she could absorb the sense of what it was like for him to grow up there.

“He was always totally supportive. However, I can’t help but believe this must have been very hard for him. After all, this was his very personal story. It was his mother and his writing that I’m using to make this film. It doesn’t get any more personal than that.”