Image copyright Getty Images Image caption Berry said she was keen to create "more opportunities for people of colour"

Halle Berry was the first black woman to win the best actress Oscar when she won for Monster's Ball in 2002.

Fifteen years on, she still is the only black woman to have won the award - and she's not happy about it.

Speaking in Cannes last week, the actress said she had been "profoundly hurt" when no black stars were nominated for major acting awards at the 2015 Oscars.

Her comments have been followed by the Academy announcing it is inviting 774 new members from 57 countries in an effort to boost diversity.

Actors Naomie Harris, Riz Ahmed and Warwick Davis are among those invited to join, with the Oscars organisers saying 39% of the new class are women, boosting the overall female membership to 28%, up three points from 2015.

It added that the new membership is also nearly a third non-white, with the number of non-white voters now at 13%, up from 8% two years ago.

Image copyright Getty Images Image caption The X-Men and Catwoman star was named best actress at the 2002 Oscars

"It was probably one of my lowest professional moments," said Berry of the 2015 Oscars.

The 50-year-old told Teen Vogue's Elaine Welteroth said she had thought back to the night she won her Academy Award and thought: "Wow, that moment really meant nothing."

"I was profoundly hurt by that and saddened by that and it inspired me to try to get involved in other ways," she continued.

"Which is why I want to start directing, I want to start producing more [and] I want to start being a part of making more opportunities for people of colour."

On the night in question, Berry dedicated her win to "every nameless, faceless woman of colour who now has a chance because this door has been opened".

Image copyright Getty Images Image caption Dorothy Dandridge was the first black actress to be nominated for the best actress award

Since her victory, though, only four black actresses have been nominated for the best actress Oscar.

They include Viola Davis - winner of this year's best supporting actress Oscar - and Ruth Negga, who was nominated this year for Loving.

Precious star Gabourey Sidibe and Quvenzhane Wallis, the young lead in Beasts of the Southern Wild, were also shortlisted for the best actress award in 2010 and 2013 respectively.

Four nominations in 15 years is hardly something to write home about. Yet it's worth remembering that in the 72 years of Oscar ceremonies before Berry's win, only six black actresses had ever been up for her award.

Two of those nominations came in 1973, when Diana Ross and Cicely Tyson - nominated respectively for Lady Sings the Blues and Sounder - lost out to Cabaret's Liza Minnelli.

#OscarsSoWhite

Before that the only black actress to come within touching distance of the statuette was Dorothy Dandridge, who was nominated in 1955 in Carmen Jones.

Four black men have won the best actor Oscar since the first ceremony was held in 1929, while nine more have been nominated.

The issue of black representation at the Academy Awards became a matter of public concern in 2015 and 2016, years in which no person of colour was nominated for any of the acting prizes.

This led to the "OscarsSoWhite" campaign and moves by the Academy to make both its membership and nominations more diverse.

So is Berry right to feel aggrieved? We put that question to Sarita Malik, a professor of media, culture and communications at London's Brunel University who specialises in diversity and screen media.

"What Halle Berry says reveals the burden of representation that has historically been placed on black actors, films and representations more widely - the idea these have to deal with the persistent problem of under-representation," she told the BBC.

"Her disappointment has come to characterise our expectations, where we are led to believe that more and better kinds of diverse representation will follow these rare successes.

Image copyright Getty Images Image caption This year's acting Oscars were evenly divided between black and white performers

"The Oscars is a big deal because of its international profile, its legacy and as a barometer of the cultural mood," she continued.

"If the Oscars is virtually all-white, as historically it has tended to be, this says something about the kinds of culture we celebrate and support. But it also reveals the kinds of films that are commissioned, funded and made visible through marketing and distribution.

"The past couple of years have usefully brought to the fore important public debates about diversity in the film industry and it is a positive step that the Academy's membership is being broadened.

"It's important that there is more diversity in leadership but also that, rather than churning out more and more diversity initiatives, the question of why such inequality exists is tackled head-on."

Gaylene Gould, writer and head of cinemas and events at BFI Southbank, believes Berry is right to speak out.

"She's the only black actress to ever receive a best actress award in the whole history of Oscars so of course she's justified," she told the BBC. "I can totally see why she's depressed."

Image copyright Selznick/MGM/Kobal/REX/Shutterstock Image caption Hattie McDaniel, pictured with Clark Gable, was the first black actress to win an Oscar

Gould also believes it's significant that while Berry remains the sole best actress winner, seven black actresses have been named best supporting actress.

"If a black woman is going to get something it will be best supporting actress," she said. "It rarely goes higher than that."

Hattie McDaniel was the first black actress to be named best supporting actress, winning for Gone with the Wind in 1940.

The next was Whoopi Goldberg, who won the award for Ghost more than half a century later. Her 1991 award came five years after she was nominated for the best actress award for The Color Purple.

"There is a question there about where we position women, where we position black women and how seriously they're taken in cinema," Gould continued.

"A lot of what we do at the British Film Institute is all about how you create opportunities and systemically change the fundamental trends within the sector."

Last year the BFI launched its Black Star season, a three-month, UK-wide celebration of black screen talent.

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