To screenwriters in the 1950s, she was a major power player, fighting for pay rises and striking rights. To the Hollywood studio heads, she was “the meanest bitch in town”.

Now, a new book aims to restore Mary C McCall Jr’s reputation as one of the film industry’s most important figures, a trailblazer who was airbrushed from history after getting on the wrong side of movie moguls.

Prof J E Smyth, whose book, Mary C McCall Jr: The Rise and Fall of Hollywood’s Most Powerful Screenwriter, will be published in September, said: “[McCall] was targeted by right-wing men who didn’t like the amount of power she had had during the 1930s and 1940s and they were going after her …

“The Hollywood blacklist cleaned a lot of women out of the industry, and she was one. Then historians and film critics erased her, because all they’ve ever cared about is great male directors … At McCall’s death in 1986, aged 81, archives did not even want her papers, and she has simply been forgotten. Material relating to women was just deemed not worthwhile.”

Smyth, professor of history at the University of Warwick, discovered material in the archives of Warner Bros, the Academy of Motion Picture Arts and Sciences and the Writers Guild Foundation, as well as private collections, that shed new light on McCall, who became the first female president of the Screen Writers Guild in 1942.

Smyth unearthed letters and an unpublished memoir that McCall wrote for her children about her career, as well as records of the work she did for female screenwriters who were having difficulty maintaining credit, or getting paid equally by producers. She said: “The material was there, but … none of the people who were writing about the Hollywood studio system wanted to actually deal with it.”

Smyth added: “We’re so wedded to the narrative of the golden age of Hollywood being about gorgeous women who do what they’re told, and the male moguls who were running the show, that between 1920 and 1960 women were only ever talked about if they were objectified on screen … There was also an assumption that most of the scripts were written by men. “But it’s total rubbish. Half of all cinematic employees within Hollywood were female and they could do just about anything in the business, including being producers. A quarter of all screenwriters were women – more than now.”

As a screenwriter, McCall wrote for Warner Bros, Columbia Pictures and Metro-Goldwyn-Mayer. Her films included Craig’s Wife, a 1936 box-office success about a woman who marries for money not love – a nuanced critique of marriage and sexual inequality – and she was friends with actors including Bette Davis and Humphrey Bogart.

She also launched the successful Maisie series in 1939, writing or co-writing eight of the 10 films about a wise-cracking working-class showgirl, played by comedian Ann Sothern, a role that turned her into one of the biggest stars of the 1940s.

Smyth said: “It was an early franchise that became really popular. While major Hollywood films – for example, Gone with the Wind from 1939 – played primarily in lavish cinemas in big cities, Maisie played primarily in small-town cinemas and had a loyal fanbase, driven by women who finally were seeing a woman on screen who was like them.

“Maisie didn’t wear designer clothes, she didn’t have a top hairdresser, she didn’t have perfect makeup. She had to put up with a lot of crap from men – and women loved it.” McCall also campaigned for fellow writers, said Smyth.

“She [led] a fight to unionise the industry’s writers and secure the first contract guaranteeing a minimum wage, credit protection and pay raises, as well as the right to strike. She was a power player. To studio heads she was, in the words of Jack Warner, ‘the meanest bitch in town’.”

In a legal case against mogul Howard Hughes, the head of RKO Pictures studio, McCall defended a writer he had fired for being subpoenaed to appear before the House Committee on Un-American Activities, which conducted investigations during the 1940s and 1950s into alleged communist activities.

McCall said: “I did not intend to permit Mr Hughes to trample on a labour agreement with muddy tennis shoes.” But in 1979, she spoke of her belief that Hughes had played a part in destroying her career, persuading other producers not to hire her. “As a consequence … I was unable to find work.”

Smyth hopes to put McCall back in her rightful place in the history books. “Historians that started to write about Hollywood in the 1960s were the ones who really cut women out of the story of Hollywood,” she said.