Joseph Stalin

Joseph Stalin, also spelled Josef Stalin, was a communist dictator of the Soviet Union. He served as the General Secretary of the Communist Party of the Soviet Union. (PROSE: History 101)

Stalin, Winston Churchill and Franklin Delano Roosevelt once met at Yalta. (PROSE: Beguine)

The Seventh Doctor visited an old man named Josef who had been president of his country for decades. He told Josef that, though people would vilify him for over a century, they would eventually realise that his actions were the right thing to do, and they would continue his work. Grigori subsequently slipped something into Josef's drink. (PROSE: Closing the Account)

Alternate timeline
In an alternate timeline, Simon Brown shared the secrets he had learned about atomic bombs with the world. Fearing every nation having access to atomic weapons, Stalin bombed the planet, and the political organisation known as "the Party" took over. (PROSE: The Winning Side)

Personality
It was said that Stalin liked to listen to the sound of mad dogs barking. (PROSE: Endgame)

Behind the scenes

 * According to The Brilliant Book 2012, a book that contains non-narrative based information, in an alternate universe where all of history happened at once, Stalin played live chess with Cleopatra.
 * He was played by Brian Cox in an episode of Thirty-Minute Theatre, David Bradley in an episode of Theatre Night, Bernard Kay in an episode of Screen Two and Simon Russell Beale in the play Collaborators.