In the 50 years that Star Trek has been around, the franchise has shifted direction multiple times. New showrunners have come and gone with each TV series, and major characters have had their backgrounds obscured, retconned, or remade entirely as time has gone by. Writers have done their best most of the time to keep all the thousands of characters, locations, starships, and events in sync with each other. Even major mysteries like the change in the appearance in Klingons between Star Trek: The Original Series and the rest of Star Trek being addressed eventually (then gleefully cast aside for Star Trek: Discovery).

Some moments in Trek have been retconned or forgotten without any explanation. For one reason or another, whether it be ignorance or convenience, writers have taken details both major and minor and made them poof into the proverbial transporter beam. Below we've gathered a few of the facts and histories of Star Trek that were canon before they inexplicably weren't anymore.

James R. Kirk - The Original Series

In the second pilot of Star Trek: The Original Series, Kirk and the crew of the Enterprise face off against fellow crewman (and Starfleet Academy friend of Kirk) Gary Mitchell. Mitchell gains psionic powers after the ship passes through the Great Galactic Barrier, and eventually goes mad.

When the Enterprise enters the orbit of a planet to make repairs, Mitchell transports to the surface, and Kirk chases him. In an attempt to intimidate Kirk, Mitchell materializes a tombstone with his powers that reads "James R. Kirk." However, later in The Original Series Kirk's middle initial is changed to "T," which we find out in The Animated Series stands for "Tiberius."

The whole incident is never mentioned again, and a non-canon explanation could be that Gary Mitchell just forgot Kirk's middle initial in the throes of his megalomania. However, given that Mitchell and Kirk were such good friends, the more likely answer is that the next writer to use Kirk's middle initial just forgot about the "R" in Where No Man Has Gone Before. Kirk doesn't remark on the initial being wrong in the episode and given that a year passed between filming Where No Man Has Gone Before and the next episode, The Corbomite Maneuver, it was likely just a fact that never got passed along.

Every Starship has its Own Insignia - The Original Series

This subject matter fits somewhere in-between inconsistencies, apocrypha, retcon, and fan theory and has been a subject of speculation and debate for the Star Trek fanon for decades. The classic argument goes that the Enterprise delta insignia was unique to that ship and that each ship in Starfleet had its own special uniform badging.

If you search for "The Original Series Ship Insignia" you'll see droves of fan-made badging for ships we saw on-screen, but never saw the crew of, and hundreds of non-canon ships. This theory was so strong that it was taken as fact by almost every piece of reference material about Star Trek printed in the last fifty years. There's just one issue with the whole thing: the theory is entirely wrong.

The iconic Starfleet delta emblem on the iconic Captain Kirk.

A few years ago UCLA Irvine was digitizing memos and other documents held in the Gene Roddenberry Television Series Collection when they discovered a memo from Bob Justman, supervising producer on Star Trek: The Original Series dated December 18, 1967. The memo is to costume designer Bill Theiss concerning the about-to-air episode "The Omega Glory." In this episode, the Enterprise finds the drifting USS Exeter's crew dead, and on their uniforms, where the Enterprise delta was normally placed, was a badge never seen before.

The problem goes all the way back to the first regular episode of Star Trek shown on TV, "Charlie X." In this episode, we see two of the crew of the Antares, who are wearing the uniforms of Starfleet but with a unique insignia on the breast. Bill Theiss, when designing the costumes for "The Omega Glory," interpreted this badging to be a unique icon worn just by the crew of the Antares. That wasn't the case though.

Justman's memo explains:

"Whilst sitting in Dailies today, it was noticed that a Starship Captain (from another Starship) was wearing an emblem unfamiliar to yours truly. I have checked the occurrences out with Mr. Roddenberry, who has reassured me that all Starship personnel wear the Starship emblem that we have established for our Enterprise Crew Members to wear.

Doubtless this situation has arisen due to the fact that a different Starship emblem was used last season on "CHARLIE X". However, the personnel of that other ship in that show were the equivalent of merchant marine or freighter personnel -- and therefore not entitled to bear this proud insignia on their individual and collective breasts.

Please do not do anything to correct this understandable mistake in the present episode. However, should we have Starfleet personnel in any other episodes, please make certain that they wear the proper emblem."

So what about the other Starfleet personnel we see wearing different emblems during The Original Series? It turns out the situation with them is similar to that of the Antares icon. The different insignia seen throughout the rest of the original run of Star Trek denote what branch of Starfleet an individual serves under. There's the starburst of Starbase duty personnel, the smaller starburst of Starfleet Academy cadets, the outpost duty emblem of those who serve on the edge of Federation space, Commodore Matt Decker's Flag Officer on field duty icon, and the most iconic: the delta of personnel assigned to Starship duty.

While I wasn't too excited to accept that such a seemingly established Star Trek factoid was patently incorrect, Justman's memo and the information presented on the official Star Trek website take precedent. It says a lot for how ingrained this was in Trek culture that when "In a Mirror, Darkly" was being produced for Star Trek: Enterprise, a new emblem was created for the deceased crewmembers of the USS Defiant even though the original crew wore the correct delta insignia of Starship duty officers.

The Klingons and the Federation Are/Aren't Allies - Star Trek: The Next Generation

While the Klingons were never the antagonistic and cantankerous lot that we saw in The Original Series, The Next Generation (and subsequent productions) never portrayed the Federation and the Klingons as having anything close to a political union. However, two relatively minor parts of two Star Trek: The Next Generation episodes leave the producers' intentions for the Federation's relationship with the Klingons somewhat nebulous.

In the ST:TNG season one episode "Heart of Glory," we get our first peak of a Klingon bridge in this series. Alongside the emblem of the Klingon Empire, flanking the Klingon captain, is the seal of the United Federation of Planets. This indicates some deeper union than is shown later in the series, as it appears the seal is placed in a position of equal importance to the Klingon's insignia. We also never see this sort of arrangement again on a Klingon vessel, which makes it appear as though it had some significance here that was later disregarded.

The second on-screen clue as to the producers of ST:TNG's plans for a stronger union between the Federation and the Klingon Empire is a line in the second season episode "Samaritan Snare." Captain Picard and Wesley Crusher are on a shuttlecraft, and Picard is recounting the story behind how he got his artificial heart. Wesley interrupts him to ask, "Was this before the Klingons joined the Federation?" Picard replies in the affirmative and nothing about the Klingons "joining" the Federation is ever brought up again for the rest of the show and the series that follow.

Some have said that maybe the Klingons "joining" the Federation is an indicator of some non-aggression or mutual defense pact, but two things make that a toothless argument. For one, whenever any character in the history of Star Trek talks about a planet becoming part of the United Federation of Planets, they refer to it as "joining." In Deep Space Nine they talk about Bajor "joining" the Federation about a hundred times.

The whole picture becomes clear if you glance at pages 35 and 36 of the writer/director's bible written for season one by Gene Roddenberry. There's a section titled "The Federation is an Alliance of Many Planets" that reads:

"The Federation is not a human-only alliance. Many worlds, human and otherwise, have joined together to form a Federation of mutual benefits and services. Starfleet vessels serve all the worlds of the Federation, not simply Earth. By the time of the 24th century, there are as many alien worlds in the Federation as human. Quite recently, for example, Klingon joined the Federation, and we have begun to see Klingon officers in Starfleet."

As this section is talking about the Federation member worlds, it's evident that at least at the beginning that the Klingons were intended to be full members of the United Federation of Planets. (As a side note, it seems "Klingon joined the Federation," may be referring to the Klingon homeworld, which hadn't been properly named at the time.)

One of the reasons the Klingons might have been semi-retconned into a separate political entity again is because TNG just didn't have a lot of steady sources of intrigue. The Ferengi were being set up as adversaries of the Federation starting with their first appearance in the season one episode "The Last Outpost," but they fell flat with audiences, and by the time Season 3 rolled around, they had been mainly regulated to minor enemies and comic relief.

To fill the void the Ferengi left, the Klingons were portrayed as the cold-at-times neighbor of the Federation. The two powers were shown as being mutually respectful for the most part, but the Klingon Empire constantly fluctuated in stability, which threatened Federation interests. Really, we lucked out, because the storylines featuring the Klingons in The Next Generation and Deep Space Nine were some of the best of both series.

Any weird Star Trek plot threads that bug you? Let us know in the comments.