Scarlett Johansson has praised the Me Too movement for bringing hope of equality as she addressed thousands who joined Women’s Marches on the anniversary of Donald Trump’s inauguration as US president.

She told an estimated 500,000 protesters in Downtown Los Angeles on Saturday how the Harvey Weinstein revelations led her to consider how she had been treated as a young actress.

Wearing a Time’s Up top, she said: “As the rage settled in it gave way to other feelings – sadness and, unexpectedly, guilt and grieving.

“Suddenly I was 19 again and I started to remember all the men I’d known who took advantage of the fact I was a young woman who didn’t yet have the tools to say no.”

Scarlett Johansson
Johansson says viewers must lead the way (Ian West/PA)

Many of her relationships, both personal and professional, had power dynamics “so off” that she let herself be “degraded”, she said.

“I stand before you as someone who is empowered not only by the curiosity about myself and by the active choices that I’m finally able to make and stand by, but by the brightness of this movement, the strength and the unity that this movement has provided,” she said.

“It gives me hope that we are moving toward a place where our sense of equality can truly come from within ourselves.”

She was among Hollywood stars joining marchers marking a year since more than one million people worldwide rallied on Mr Trump’s first day in the White House.

The latest demonstration comes at a time of reckoning for many powerful men in Hollywood and other industries over their treatment of women, courtesy of the Me Too movement.

Viola Davis shared her own experiences to echo the march organiser’s sentiment to encourage people to sign up to vote in November’s mid-term elections, which could deal a blow to the president.

“I’m always introduced as an award-winning actor but my testimony is one of poverty, my testimony is one of being sexually assaulted and very much seeing a childhood that was robbed from me,” Davis said.

“I know that the trauma of those events are still with me today and that’s what drives me to the voting booth, that’s what allows me to listen to the women who are still in silence.”

Eva Longoria told protesters to seize the Me Too momentum to fight for equality and decried the “sexist, racist rhetoric” coming out of the White House.

“As we build upon the momentum of Me Too and Time’s Up in this movement, we women have the world’s attention so let’s seize this moment and catalyse a permanent and cultural shift towards fairer and equal treatment in the workplace,” she said.

Alfre Woodard said that people must reach across boundaries to fight for a common cause in this “dangerous and baffling hour”.

Many at last year’s rallies focused their outrage on Mr Trump’s policies and alleged behaviour, which includes denied claims of sexual assault by multiple women and his boasting of grabbing women “by the pussy”.

The pink, pointy-eared “pussy hats” used to mock the commander-in-chief made a popular return.

As hundreds of thousands took to the streets, Mr Trump tweeted that it was a “perfect day” for women to celebrate the “economic success and wealth creation” of his first year in the White House.

The marchers disagreed.

Anti-Trump sentiments were strong among the placards, but so were pro-immigrant messages and those in favour of women’s rights, including one reading “Girls just want to have fun-damental rights”.

The main march this year was held in Las Vegas, but others took to the streets in cities including New York City and Washington DC.

UK cities will hold marches on Sunday including a London demonstration in support of the Time’s Up initiative.