Joseph Stalin
Josef was the president of his country for several decades. During that time, he met the Seventh Doctor several times.
When Josef was dying, he captured Ace to force the Doctor to visit him. He had figured out that the Doctor could see his future and wanted to know what his legacy would be. The Doctor told him that for over a hundred years, people would vilify him, but after that, people would realise that his actions, though sometimes wrong, were the right thing to do and they would continue his work. The Doctor watched as Josef's servant, Grigori, put something in Josef's drink. (PROSE: Closing the Account)
Behind the scenes
Josef is almost certainly a reference to Joseph Stalin.