Before the Common Era (Columbia)

c.5 Billion BCE

• Chapter 11 (TNG #47: "The Q Continuum, Book One: Q-Space")
• Vulcan: One (TOS: "Spock's World")
• "Reciprocity" (TNG: "Strange New Worlds II"

c.2.5 Billion BCE

• Chapter 13 (TNG #47: "The Q Continuum, Book One: Q-Space")

c.1 Billion BCE

• Chapter 2 (TNG #48: "The Q Continuum, Book Two: Q-Zone")

444,800,000 BCE

• Chapters 12, 17, 19, 23 (VOY) #2: "The Escape"

64,018,143 BCE

• Chapters 23-38 (TOS #75: "First Frontier")

500,000 BCE

• Vulcan: Two (TOS: "Spock's World")

307,600 BCE

• Chapters 4-7, 23 (VOY) #2: "The Escape"

27,600 BCE

• "Horn and Ivory," chapters 1-9 (DS9: "Gateways: What Lay Beyond")

10,000 BCE

• Vulcan: Three (TOS: "Spock's World")

7954 BCE

• (TOS: "Ex Machina"

4527 BCE

• A Caeliar city-ship is accidentally transported back in time from 2168 with several survivors of the Columbia NX-02 crew. One of the Caeliar survivors, desperately trying to stave off death, forces a bonding with the Humans, resulting in the formation of the Borg Collective. (ENT/TNG/DS9/VOY/TTN: "Destiny, Book Three: Lost Souls")

3000 BCE

• Vulcan: Four (TOS: "Spock's World")

c.2705 BCE

• Ancient Past (TOS 78: "All Our Yesterdays")

2703 BCE

• Chapters 5-6 (TOS #11: "Yesterday's Son")

2683 BCE

• Prologue, Chapters 5-10, 14-15 (TOS #39: "Time for Yesterday")

235 BCE

• Chapter 11 (TOS #21: "Uhura's Song")

30 BCE

• Vulcan: Five (TOS: "Spock's World")

Next: Chronology: Time of Awakening and the Sundering