There ae significant chronological problems with Romulan-Federation relations during the TOS era.
The opeing credits of each TOS episode mention the "five year mission".
In
Star Trek: The Motion Picture, which happens at least 2.5 years after the last episode of TOS, and maybe as much as a decade later, tKirk mentions having spend five years out there facting the unknown.
So it is logical to deduce that TOS episodes probably happen during one single five year mission. And to be called five years it must have been at least a little bit longer than four point zero years, and at least a little shorter than six point zero years.
So did the five year mission include the three seasons of TOS, or the three seasons of TOS pluse the one or two seasons of TAS?
If there are three to five season in four to siz years, then there are about zero point eight to two point zero years per season.
And what order did the episodes happen in?
Commonly suggested orders for TOS and/or TAS episodes are:
one) original broadcast or airdate order.
Two) production order (defined as order of filming the scenes with actors on sets).
Three) stardate order.
And:
Four) In order of seasons, and by order of stardates within each season.
But what if there is no intended order for TOS episodes to happen in? What if the original creators assumed that the episodes could happen in any old order (except for the very few episodes which mentioned events in earlier episodes)?
In that case, for most randomly selected pairs of TOS episodes the most we could say would be that episode A must be no more than six years at the very most before or after episode B.
In "Balance of Terror" nobody in the Federation knows what Romulans look like. So obviously there aren't Romulans who look like Vulcans on Nimbus III mingling with setters from the Federation and the Klingon Empire yet. Otherwise everyone would already know that Romulans look like Vulcans.
And I think that there couldn't be any settlers from any subject planets in the Romulan Empire on Nimnus III yet. Otherwise they would sometimes tell people from the Federation what their Romulan overlords look like. Unless the Romulans never meet any subject beings personally and keep their true appearance secret for some reason.
So there should be no settlers from the Romulan Empire on Nimbus III at the time of "Balance of Terror", and so, unless the Romulans joined the Nimbus III agreement a long time after the Federation and the Klingons did, the Nimbus III treaty should have happened after "Balance of Terror", or else in an alternate universe to it.
Kirk finds Khan in "Space Seed" and decides to plant Khan and his followers an Ceti Alpha V at the end of the episode.
In
Star Trek II: The Wrath of Khan both say it is fifteen years since they saw each other. It is usually assumed that they haven't seen each other since Kirk seeded Ceti Alpha V with Khan's people soon after "Space Seed". But it is psosible that Kirk and Khan saw each other again a few years after "Space Seed" in some unseen event, and that could be used as an explanation of the chronological problem.
All the movies from
Star Trek II: The Wrath of Khan through to
Star tTek V: The Final Frontier seem to happen within just a few months of fictional time. It is always possible to put extra time in there by supposing, for example, that the ending of
Star Trek IV: The Voyage Home where Kirk e gets the Enterprise-A i months or years after the trial sequence when Kirk is demoted to captain, or that after the Enteprise-A starts its shakedown cruise at the end of
Star Trek IV: The Voyage Home it encounters a time warp which sends it a few months or years into the future before
Star Trek V: The Final Frontier begins.
But unless you specify a specific theory that something like that happens, all the movies from
Star Trek II: The Wrath of Khan through to
Star Trek V: The Final Frontier happen over just a few months of fictional time.
So the official
Star Trek Chronology: The History of the Future makes a big error by stating that
Star Trek II: The Wrath of Khan happens in the year 2285,
Star Trek III: The Search for Spock also happens in 2285,
Star Trek IV: The Voyage Home hppens in 2286, and
Star Trek V: The Final Frontier happens in 2287 witout specifying what would have stretched out the series of events so much. It is natural and reasonable to believe that the events of those four movies happen over only a few months of fictional time.
But in
Star Trek V: The Final Frontier Romulan representative Caithlin Dar says:
CAITHLIN: Twenty years ago, our three governments agreed to develop this planet together. A new age was born.
Possibly everyone who checked this thought that since it was 1989, 23 years since "Balance of Terror" was aired, there was time for the Nimbus III agreement to be signed after "Balance of Terror" and twenty years before
Star Trek V: The Final Frontier.
But what needed to be accurate was the interval in fictional time between "Balance of Terror" and
Star Trek V: The Final Frontier, not the interval between their production in the real world.
Possible explanations of the chronological problem:
One:
Possibly
Star Trek II: The Wrath of Khan happened fifteen Earth years after "Space Seed", and
Star Trek V: The Final Frontier happened twenty Romulan years after "Balance of Terror", thus making a Romulan year about zero point seven five Earth years long. (And psosibly Caithlin Dar rounded up from nineteen or eighteen Romulan years to twenty Romulan years. But the fifteen years mentioned by Kirk and Khan seem too precise to have been rouned up or down much.)
TWo:
Possibly there was an unmentioned time skip somewhere in the sequence of four movie so that
Star Trek II: The Wrath of Khan happens a few years instead of a few months before
Star Trek V: The Final Frontier.
As i wrote above:
It is always possible to put extra time in there by supposing, for example, that the ending of Star Trek IV: The Voyage Home where Kirk gets the Enterprise-A i s months or years after the trial sequence when Kirk is demoted to captain, or that after the Enteprise-A starts its shakedown cruise at the end of Star Trek IV: The Voyage Home it encounters a time warp which sends it a few months or years into the future before Star Trek V: The Final Frontier begins.
Three:
Possibly
Star Trek II: The Wrath of Khan actually happened twenty years after "Space Seed", because Kirk did check up on Khan at Ceti Alpha V once, five years after "Space Seed".
As I wrote above:
In Star Trek II: The Wrath of Khan both say it is fifteen years since they saw each other. It is usually assumed that they haven't seen each other since Kirk seeded Ceti Alpha V with Khan's people soon after "Space Seed". But it is psosible that Kirk and Khan saw each other again a few years after "Space Seed" in some unseen event, and that could be used as an explanation of the chronological problem.
Four:
Possibly "Balance of Terror" happens in an alternate universe where the Romulans are more hostile, and that "Space Seed" and the movies from
Star Trek II: The Wrath of Khan through to
Star Trek V: The Final Frontier happen in a didferent alternate universe where the Romulans establish more normal relations with the Federation instead.
As I wrote above:
...the Nimbus III treaty should have happened after "Balance of Terror", or else in an alternate universe to it.
Five:
Possibly the Romulans sent settlers from their subject planets to Nimbus III before "Balance of Terror", but those settlers didn't know what Romulans looked like because the Romulans kept their true appearance secret from their subjects somehow.
As I wrote above:
Unless the Romulans never meet any subject beings personally and keep their true appearance secret for some reason
Six:
Possibly Nimbus III was established years before "Balance of Terror", but the Romulans didn't join the agreement or send settlers until years after "Balance of Terror" and "Space Seed".
As I wrote above:
So there should be no settlers from the Romulan Empire on Nimbus III at the time of "Balance of Terror", and so, unless the Romulans joined the Nimbus III agreement a long time after the Federation and the Klingons did, the Nimbus III treaty should have happened after "Balance of Terror", or else in an alternate universe to it.
Unless a chronology of
Star Trek explicitly includes one of thsoe six possible explanations, it has a problem making the time spans between "Blalance of Terror", "Space Seed",
Star Trek II: The Wrath of Khan, and
Star Trek V: The Final Frontier add up consistently.
I suggested above that TOS epsiodes might not be intended to happen in any partulcar order. Thus the only thing that we could say for certain about "Balance of Terror" and "Space Seed" is that "aBlance of terror" could be no more than six years before or after "Space Seed"
If "Balance of Terror" can be as much as six years before "Space Seed", it would be as much as twenty one years before
Star Trek V: The Final Frontier, and thus Dar's twenty years could be correct. But of course if "Balance of Terror" could be as much as six years after "Space Seed", it could be a few as nine years before
Star Trek V: The Final Frontier, making the chronological problem much worse.
But if somone wants to put the TOS (and possibly also the TAS) episodes in one of the commonly used orders, such as airdate order, production order, or stardate order, there will be some limitations on how long before "Space Seed" "Balance of Terror" can happen. And possibly similar limitations on how long before
Star Trek V: The Final Frontier Star Trek II: The Wrath of Khan can be. And the sum of those two time spans would be the possible time span for making
Star Trek II: The Wrath of Khan fifteen years after "Space Seed" and
Star Trek V: The Final Frontier twenty years after "Balance of Terror".
So anyone working on a chronology of
Star Trek has to make the intervals between "Balance of Terror", "Space Seed",
Star Trek II: The Wrath of Khan and
Star Trek V: The Final Frontier the proper lengths, which would be easier with some chronological assumptions than with others..
