The Duke of Cambridge has been the president of the British Academy of Film and Television Arts since 2010, when he took over from Sir David Attenborough.
The ceremony is the biggest event in the British film calendar each year and the stand-out victor last night had a royal connection.
Kate, 37, channelled Hollywood glamour in a white one-shoulder gown with tulle flowers embroidered on one shoulder.More news: Measles making comeback on widening anti-vaccine movement
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Attending the awards ceremony, Kate made a tribute to William's late mum, Princess Diana, by wearing her favourite earrings to the function.
Special guests of the occasion were the Dukes of Cambridge - Prince William and Kate Middleton.
Kate Middleton wore Alexander McQueen to BAFTA 2019. But Will and Kate being the polite Brits they are (who have also conveniently not yet factored into The Crown's narrative), welcomed Colman with open arms on the red carpet.
Actor Rami Malek picked the Best Actor BAFTA for Bohemian Raphsody while Mahershala Ali won Best Supporting Actor for Green Book.