The day the Princesses vanished was the last day of peace. Nopony was the same when the sun and the moon continued their way across the sky without the Princesses' magic. With that apparent lie exposed, Equestria was in shambles for weeks, months even.
Everything slowly took a turn for the worse, starting with the betrayal of the Element of Honesty. Nopony really knows what happened that day, except for the other Elements of Harmony. Equestria is shattered.
Five uneven pieces.
Equestria is divided. And it has been so for fifteen years.
We're just the many insignificant ones. This is our lives, stuck in Tartarus.
(The setting belongs to PoorYorickDA, who created this awesome thing that is Equestria Divided)
(This is a one-shot so far, done purely to promote what I believe is a well thought-out grimdark Equestria, but it might evolve into a bigger story someday)