Feminist activists were brought onto the red carpet as dates to the BAFTAs.
Arterton was accompanied by former sewing machine operators Eileen Pullen and Gwen Davis, who staged a three week walk-out at a Ford plant in 1968 after learning they were paid 15 percent less that their male counterparts, and Riseborough brought trade unionist and co-founder of U.K. Black Pride Phyll Opoku-Gyimah.
Best Leading Actress winner Frances McDormand, who did not wear black, offered her support to the Time's Up movement onstage while accepting her award.
"I want you to know that I stand in full solidarity with my sisters in black. I appreciate well-organized civil disobedience," she said.
McDormand's "Three Billboards Outside Ebbing, Missouri" co-star Rockwell, who won the award for Supporting Actor, also spoke of the Time's Up movement onstage saying that he "stands on the shoulders of women, strong, intelligent and righteous women," adding that it was "important to represent, important to listen. It's respectful."
"As we approach the Baftas - our industry's time for celebration and acknowledgment, we hope we can celebrate this tremendous moment of solidarity and unity across borders by coming together and making this movement international," the letter said.
"There is no question that Time's Up should be and will be a global movement," it continued.
"A movement that is defined and led by those affected by the problem, not by those in power."
Copyright 2018 United Press International, Inc. (UPI). Any reproduction, republication, redistribution and/or modification of any UPI content is expressly prohibited without UPI's prior written consent.