TV There are many, many lists online offering tips on how to watch Star Trek in chronological order. This is my favourite because of the way it weaves the episodes in and out, especially around the Maquis storyline which kicks off Voyager. But there many others, so there would be little point in me trying to do another in the style of my Doctor Who list.
But something I've often wondered is if it would be possible to create a watchable pre-history for Star Trek, collecting together all of the time travel and flashback episodes from across the franchise pre-Enterprise and dropping them into chronological order. Turns out that yes, you can, but there aren't as many as you would think.
Much of the time when Star Trek does time travel its within the window of the show's own history from Enterprise through to Discovery 2.0, it doesn't travel much further back very often and when it does, it's sometimes into alternative timelines in which aliens are pretending to be Nazi and that sort of thing. Or it's a dream sequence as per DS9's Far Beyond The Stars.
So the rule here is that the episode has to feature events which take place in the Prime timeline before the Enterprise opener Broken Bow. I did consider interpolating material from other sources based on that show's epic opening title sequence and I may still do that, but just for now let's keep this as clean as possible. So here's an excuse to watch some more Star Trek.
1863
"An engineering team finds evidence of an alien presence on Earth in 19th century San Francisco: Data's severed head, buried five hundred years ago."
1930
"Suffering from an accidental overdose of cordrazine, Doctor Leonard McCoy goes back to 1930s Earth, forcing Kirk and Spock to go after him and prevent the Enterprise and the Federation from being erased from history."
1947
"A malfunction on Quark's new ship causes Quark, Rom, and Nog to crash in the year 1947 in Roswell, New Mexico."
1958
"T'Pol tells Archer and Tucker a story about her great-grandmother and two other Vulcans, who crash landed in a small Pennsylvania town in the year 1957."
1968
"The Enterprise travels back in time to 1968, where the crew encounters the mysterious Gary Seven who claims to be sent by advanced beings trying to help Earth."
1986
"Admiral James T. Kirk is prepared to take the consequences for rescuing Spock and stealing and then losing the starship Enterprise, but a new danger has put Earth itself in jeopardy. Kirk and his crew must travel back in time in an old Klingon Bird-of-Prey to right an ancient wrong, in the hopes of saving Earth – and the Federation – from certain doom."
1996
"After encountering a Federation timeship from the future, Voyager is sent back to 20th century Earth."
2000
"Kathryn Janeway discovers the truth about one of her famed ancestors, Shannon O'Donnel, realizing that who Shannon was differs vastly from what Janeway had believed all her life."
2004
"Archer and T'Pol travel back in time to stop the Xindi-Reptilians in 21st century Detroit."
2024
"Trapped three hundred years in the past, Sisko, Bashir, and Dax find themselves confronting one of the darkest hours in Earth's history…"
2037
"An accident during an attempt to use a Xindi subspace corridor places the Enterprise in a bizarre confrontation… with itself."
2063
"Six years have passed since Captain Jean-Luc Picard was captured and assimilated by the Borg. Now, the Borg make a second attempt to conquer the Federation. Starfleet believes that Picard's experience makes him an "unstable element to a critical situation" and orders him to stay behind. But, when Starfleet's fight does not go well, Picard and the crew of the new USS Enterprise disobey orders to join the fight, following the Borg three hundred years into the past just as Zefram Cochrane prepares to launch Humanity's first warp-capable engine, the Phoenix, and make first contact with an alien race."
2143
"When he is told of the death of an old rival, Archer reflects on his days in the NX test program."