Thinking about it, there are actually a bunch of them - Marco Polo, The Crusade, The Myth Makers, The Gunfighters... not to mention ones with famous historical people more tangential to what the Doctor and co are doing (e.g., The Reign of Terror and The Massacre). I suppose, though, only Marco Polo really focuses on a single historical figure, played by a high profile guest actor, and structures the story around show-casing that figure in the way many of the modern celebrity historicals do.