Deliberate mistake: Edmund's "recollection" of seeing Henry Tudor includes the footage that the audience saw at the beginning; however, Edmund wasn't present when this happened, and thus should not be able to recollect it. Moreover, this scene occurred after Henry had escaped and was in safety, altering the details of the Battle of Bosworth Field. Clearly, the footage was added for the audience's benefit, to be able to link the injured Henry to the introductory scene at the start of the episode.
Deliberate mistake: There are several historical dates wrong in this episode. For a start, Prince George didn't become Prince Regent until 1811, and yet this is set before the Battle of Trafalgar in 1805 (as Black Adder gives Wellington some advice on it). Similarly, Wellington didn't get the title "Duke of Wellington" until 1814. Again inconsistent with being pre-Trafalgar.
Deliberate mistake: There are a lot of jokes with the name of the book "The Prince and the Pauper." However the book was published in 1881, 51 years after the Prince Regent died.
Deliberate mistake: Whenever a punch is thrown in this series, the punch either stops before it hits the person or goes beside them. It's most obvious in the last episode when General Melchett says 'Excellent native cockney wit' and punches Baldrick.
Answer: Tony Aitken played the Balladeer. Blackadder wants to kill him because he annoys him and usually sings songs about what a fool he is.
Captain Defenestrator