!!Present Across the Series
* RealitySubtext: Creator/StephenFry's homosexuality is amusingly alluded (and PlayedForLaughs) to by some of his characters' actions:
** Lord Melchett (''Blackadder II'') had a very... close relationship with Flossie the sheep.
** His interpretation of Lord Wellington (''BA The Third'') is pretty much CampStraight.
** General Melchett's "one true love" was Speckled Jim, his pet pigeon. In another episode he falls for George's drag act, and considers a woman's "drag act" a disaster.
* StarMakingRole: For Tony Robinson in the UK.
* WhatCouldHaveBeen: One idea for a fifth series would have had Blackadder as a member of Margaret Thatcher's cabinet in the 1980s.
** Another idea was to do a UsefulNotes/WorldWarII prisoner escape story.
** Yet another was ''The Red Adder'', with Blackadder being a secret policeman in Russia during the Revolution. It would turn out that by the end of the series, he'd be doing the same job only in a different uniform.
** A fifth series or a movie set in the TheSixties about a rock band was on the cards at one point but nothing came of it.
* WordOfGod: Turnips are mentioned a lot, from the second series on. In series three, they become Baldrick's only ambition in life. The creators say this is because someone confused them with parsnips, which explains the joke about their shape in series two.
* YouLookFamiliar: Tim [=McInnerny=], Miranda Richardson, and Creator/StephenFry all made guest appearances in various episodes.

!!Present in ''The Black Adder''
* CharacterAsHimself: Mad Gerald in the finale "Born to Be A King". He's played by Creator/RikMayall.
* DawsonCasting: Robert East, who played Edmund's older brother Harry, Prince of Wales, was just seven years younger than Creator/BrianBlessed, who played his father, King Richard IV.[[note]] Some websites confuse him with a different Robert East who was actually nearly five years ''older'' than Blessed.[[/note]]
* OldShame: Rowan Atkinson and producer John Lloyd spend a significant amount of time badmouthing this series in the documentary included on the DVD boxset, calling it "pretty, but dreary to watch."
* ThePeteBest:
** Creator/BrianBlessed (Richard), Elspet Gray (Gertrude), Robert East (Henry) all qualify, as none of them would return for the later, more popular incarnations of the series (Blessed was asked back for one-off appearances in the third and fourth series, but was unavailable on both occasions).
** Going back a step further, John Savident (the King), Robert Bathurst (Henry), and Philip Fox (Baldrick) were replaced between the pilot and the series; only Rowan Atkinson, Tim [=McInnerny=], and Elspet Gray remained of the primary cast from the pilot.
* WhatCouldHaveBeen:
** The original pilot episode was much more similar to what the later ''Blackadder'' installments would be like (for example, Edmund was much more savvy and snarky in the pilot than he was in the series, except in "Born to Be King", of which the pilot was an early version), but ExecutiveMeddling resulted in the version of ''The Black Adder'' that we know and... well, treat as a valued and respected ''friend'', but not really love, per se. Most fans believe that had the finished series combined the pilot episode's characterisations with the cast that we ended up with, it would have been vastly superior.
** In "The Archbishop", [[Series/SteptoeAndSon Wilfrid Brambell]] was originally cast to play the dying landowner, the Duke of Winchester in the opening scene. However, delays while filming the scene led to Brambell getting impatient and storming off the set, resulting in his speedy replacement by [[Series/DoctorWho William Russell]].

!!Present in ''Blackadder II''
* ActingForTwo: Creator/HughLaurie shows up in the final two episodes of the season, but in two unrelated roles: in "Beer", he's Simon Partridge, one of Blackadder's jolly drinking buddies; and in "Chains", he plays the villain, the wicked Prince Ludwig. Laurie evidently must have had a good time on set, since he went on to return in the following two seasons as a major cast member.
* OutOfOrder: "Head" was originally intended to be the first episode, and was first to be filmed. This resulted in the small continuity error of Lord Percy still having a beard in "Head" which he shaves off in "Bells". In addition, during the early scenes of "Head", the principal characters are introduced to the audience with Baldrick's stupidity highlighted.
* IronyAsSheIsCast: Creator/MiriamMargolyes, who played the Puritanical Lady Whiteadder, is not only openly gay but Jewish.
* WhatCouldHaveBeen: Creator/BrianBlessed claims that the original plan was that he would have played Queenie. And been madly in love with Edmund. It's quite a terrifying idea.
** There was a murder mystery episode that was abandoned when nobody could get it to work.
** Creator/JimBroadbent was supposed to play Lord Whiteadder, again opposite Creator/MiriamMargoyles, but was unavailable.

!!Present in ''Blackadder the Third''
* ActingForTwo: In the finale, Creator/RowanAtkinson also plays Edmund's Scottish cousin [=McAdder=].
* WhatCouldHaveBeen: [=Tim McInnerny=] was supposed to play George, but turned it down for fear of being typecast, although he appeared in a guest role in "Nob and Nobility".

!!Present in ''Blackadder Goes Forth''
* ActorAllusion: In "Captain Cook", Melchett tells George that his [[Series/JeevesAndWooster Uncle Bertie]] sends his regards. ''Blackadder'' predates ''Jeeves and Wooster'', so it's a ''prescient'' Actor Allusion!
* ActorSharedBackground: Melchett and George are both implied to have gone to Cambridge, just like Creator/StephenFry and Creator/HughLaurie. (Averted with Blackadder, who didn't go to university, unlike Oxford graduate Creator/RowanAtkinson.)
* TroubledProduction / WagTheDirector: According to Creator/StephenFry and Tony Robinson, there was a lot of friction between the cast and writers during the making of this series, with the actors frequently rewriting the script on the set, which the two have admitted doing themselves. The resulting atmosphere on-set -- together with producer John Lloyd leaving the BBC and the knowledge that any hypothetical ''Blackadder 5'' would be eviscerated by the critics if it was even slightly worse than the previous series -- made it certain that this would be the final ''Blackadder'' production until ''Back & Forth'' ten years later.
* WhatCouldHaveBeen: The legendary TearJerker ending to the final episode was actually thrown together in post-production due to the scripted ending going catastrophically wrong in filming. Originally, everyone was supposed to be dramatically gunned down, with Captain Blackadder being the only survivor and sneaking away, before being seen as an old man in an epilogue scene that never got filmed. Thanks to a combination of limited filming time, the director having no experience with action scenes and there being no money for a stunt co-ordinator in the budget, it ended up being so horribly executed that the footage was unusable. As a result, the crew ended up slowing down what little usable footage they had, breaking it down into several short shots, and then crossfading to a photograph of some poppies.