The 5-Year Mission, and when it occurs in Eta Timeline
TOS Timeline
The Cage: April 15th, 2254
Where No Man Has Gone Before: June 3rd, 2265
The Corbomite Maneuver: January 12th: 2266
Mudd's Women: January 29th, 2266
The Man Trap: March 4th, 2266
Charlie X: March 13th, 2266
The Enemy Within: April 12th, 2266
The Naked Time: June 1st, 2266
Balance of Terror: June 4th, 2266
The Squire of Gothos: September 8th, 2266
What Are Little Girls Made Of?: October 15th, 2266
Miri: November 4th, 2266
Concience of the King: December 4th, 2266
Court Martial: December 12th, 2266
The Menagerie: January 5th, 2267
The Galileo Seven: January 23rd, 2267
The Devil In The Dark: February 2nd, 2267
The Return of the Archons: February 14th, 2267
Arena: March 5th, 2267
Tomorrow Is Yesterday: March 9th, 2267
Shore Leave: March 14th, 2267
This Side of Paradise: March 25th, 2267
Space Seed: April 24th, 2267
Errend of Mercy: May 3rd, 2267
The Alternative Factor: May 16th, 2267
City on The Edge of Forever: May 26th, 2267
Operation: Annihilate!: June 2nd, 2267
Chekov gets reassigned from lower decks to Bridge; promoted to Ensign: June 4
Amok Time: October 21st, 2267
The Changeling: October 30th, 2267
Who Mourns for Adonais: November 22nd, 2267
Friday's Child: November 29th, 2267
The Doomsday Machine: December 4th, 2267
Catspaw: December 9th, 2267
Metamorphosis: December 12th, 2267
Journey to Babel: December 17th, 2267
The Apple: December 23rd, 2267
Mirror, Mirror: December 26th, 2267
The Trouble With Tribbles: January 2nd, 2268
The Deadly Years: January 23rd, 2268
Obsession: February 3rd, 2268
Bread and Circuses: February 9th, 2268
A Private Little War: February 12th, 2268
Wolf In The Fold: February 16th, 2268
A Piece of the Action: February 24th, 2268
The Gamesters of Triskelion: February 27th, 2268
The Immunity Syndrome: March 14th, 2268
Return to Tomorrow: March 23rd, 2268
Patterns of Force: April 4th, 2268
The Omega Glory: April 25th, 2268
The Ultimate Computer: May 2nd, 2268
Assignment: Earth: May 25th, 2268
By Any Other Name: June 22nd, 2268
The Entropy Effect: July 5th, 2268
The Romulan Way: July 23rd, 2268
Spectre of the Gun: August 26th, 2268
The Paradise Syndrome: September 4th, 2268
The Enterprise Incident: September 25th, 2268
Elaan of Troyius: October 14th, 2268
Spock's Brain: November 12th, 2268
That Which Survives: November 23rd, 2268
Day of the Dove: December 6th, 2268
Is There In Truth No Beauty?: December 20th, 2268
The Empath: December 31st, 2268
For the World Is Hollow, And I Have Touched The Sky: January 8th, 2269
Wink of an Eye: January 14th, 2269
The Savage Curtain: February 12th, 2269
Whom Gods Destroy: February 15th, 2269
The Lights of Zetar: March 12th, 2269
The Mark of Gideon: March 20th, 2269
And The Children Shall Lead: March 26th, 2269
Requiem For Methuselah: April 9th, 2269
The Way to Eden: April 14th, 2269
The Cloud Minders: April 25th, 2269
All Our Yesterdays: April 29th, 2269
Turnabout Intruder: May 5th, 2269
Chekov and Sulu's Promotions: May 14th, 2269
More Tribbles, More Troubles: May 16th, 2269
The Infinite Vulcan: May 17th, 2269
Yesteryear: May 21st, 2269
Beyond the Farthest Star: May 23rd, 2269
Mudd's Passion: May 25th, 2269
The Pirates of Orion: May 26th, 2269
The Magicks of Megas-Tu: May 28th, 2269
The Survivor: May 29th, 2269
In Harm's Way: May 30th, 2269
To Serve All My Days: June 2nd, 2269
All The World, And Time: June 9th, 2269
Demon World: June 10th, 2269
Hijacked: June 12th, 2269
Love's Labor Jeopardized: June 14th, 2269
Another Fine Mess: June 14th, 2269
The Feathered Serpent: June 16th, 2269
That Old Devil Moon: June 19th, 2269
Vengeance: June 20th, 2269
Judgement Rites: June 22nd, 2269
The Final Voyage: June 29th, 2269
Few Contacts: July 2nd, 2269
Return Home: July 5th, 2269
The Motion Picture: December 17th, 2271
The Wrath of Khan: May 25th, 2285
The Search for Spock: December 11th, 2285
The Voyage Home: May 23rd, 2286
The Final Frontier: November 15th, 2287
The Undiscovered Country: April 25th, 2293