While Doctor Strange was definitely one of Marvel's and the year's most anticipated releases, the decision to cast Tilda Swinton as the Ancient One generated some heated controversy. In the comics, the Ancient One is a 500-year-old Tibetan man who tutors Doctor Strange in the mystical arts. While Tilda Swinton is almost certainly a 500-year-old mystic, she is decidedly not Tibetan, which led to accusations of whitewashing.
There was also speculation that the character's Tibetan origin had been dropped for fear of upsetting the Chinese government, which regards Tibet as an integral part of China. Screenwriter C. Robert Cargill seemed to confirm as much in an interview on the Double Toasted show: "If you acknowledge that Tibet is a place and that he's Tibetan, you risk alienating one billion people who think that that's bullshit and risk the Chinese government going, 'Hey, you know one of the biggest film-watching countries in the world? We're not going to show your movie because you decided to get political.'" As a result, Marvel decided to make the Ancient One Celtic in origin, with the character's Buddhist-inspired costume dropped in favor of some generic magical robes.