Unbound Doctor

This incarnation of the Doctor was exiled to Earth by the Time Lords at the end of his second incarnation. His TARDIS materialised in Hong Kong on 30 June 1997, the eve of the Handover to Chinese rule.

He could speak Mandarin, Cantonese, Manchu, Mongolian and Haikun. To the Chinese, he was known as Hu (the Tiger, for his courage), Hu (the Fox, for his cunning) and Xue (Doctor, he who tends to the sick). The last of these was his personal favourite. (NOTDWU: Sympathy for the Devil)

Behind the scenes
A bit of a myth has arisen in fandom that David Warner appeared in AUDIO: The 100 Days of the Doctor, but neither he, nor this character, appear at all in the story, though the Sixth Doctor references an alternate Doctor that may have been the Warner Doctor.