Worn by: Gary Oldman as Winston Churchill
Reference: Breguet Pocket Watch No. 765
Brand: Breguet
Winston Churchill wore a Swiss Breguet pocket watch that was originally made for his grandfather, the seventh Duke of Marlborough, and carried it almost constantly. When Breguet learned of the production, its watchmakers rebuilt the classic timepiece nicknamed "the Turnip" for Gary Oldman to wear in his Academy Award-winning performance. The yellow-gold watch is period-accurate with an enamel dial and the Duke of Marlborough's coat-of-arms engraved on the caseback—a faithful recreation minus the grand complication movement of the original, which is safely under glass at the Imperial War Museum of London.

Source: https://teddybaldassarre.com/blogs/brands/movie/references/watches