Mao Zedong

Mao Tse-Tung was a Chairman of China in the 20th century. During the preparations for the World Peace Conference, the Third Doctor mentioned to the Chinese delegate Fu Peng that he remembered having a conversation in Hokkien with Mao, at which time the Chairman allowed the Doctor to call him "Tse-Tung". (TV: The Mind of Evil)

Behind the scenes
The fact that the Doctor suggests he spoke Hokkien with Mao suggests a difference between the real world and the DWU. In real life, Mao did not speak Hokkien, as he came from deep within rural, far away from the reach of Hokkien.