The End of the Beginning…..
Coriana 6 is the location of the end of the last Shadow War where Sheridan, Delenn, and the Army of Light fought for the right of self-determination, and the freedom from the control and guidance of the Shadows and the Vorlons, who manipulated the younger races to guide their evolution.
Here, the Vorlons and the Shadows followed Lorien beyond the rim to join the rest of the First Ones who had left millions of years ago.
(cf. "Into the Fire")
This ended the Dawn of the Third Age of Mankind
and the Third Age of Mankind
In "Day of the Dead", Kosh Naranek advised John Sheridan "When the long night comes, return to the end of the beginning." This would, of course, mean that when Sheridan's extended-life was about to expire (cf. "Falling Toward Apotheosis") he would need to return to Coriana 6. (cf. "Sleeping in Light") where Lorien would escort Sheridan beyond the rim.