Once upon a time, the sun set. It was never seen again.
It has been three years since the return of Nightmare Moon during the Sumer Sun Celebration. Princess Celestia has not been seen since, and no one has ever heard of the name Twilight Sparkle or the Elements of Harmony.
However, despite being faced with this adversity, a pony learns how to adapt. The new society led by Nightmare Moon is surprisingly not that bad. In the three years since Nightmare Moon took over, there have been a remarkable amount of changes.
For one, Nightmare Moon abolished the noble system, stripping the Canterlot Elite of their titles and privileges. Many were furious about this, though some accepted it with a quiet dignity. The new ruler declared that "Effort will always surpass talent," and that the former noble ponies must re-earn their status through labor, or by providing her with results. Through this and other economic reforms, the wide gap between the rich and middle class ponies was greatly reduced.
With the new Eternal Night, many crops failed from lack of sunlight. Nightmare moon ordered all farmers to begin growing crops that thrive off of moonlight, providing many with plants and trees most have never even heard of before. The new crops have proved bountiful for those who accepted them. Those who did not were driven out of business due to failing crops. The bounty provided by these new night based crops have virtually eliminated all concerns of food shortages. Farmers can practically give their food away and still have plenty of profit. No pony ever goes hungry.
Most of the royal guard quickly submitted to their new leader after their initial attempts at defeating her were unsuccessful.
Some would even say things are better than ever.
Though, there are those who would disagree. There are many underlying problems with what Nightmare Moon has done, and the way she did it. Many ponies are unhappy, a lot for the simple reason that they remain loyal to Princess Celestia.
Various resistance groups have sprouted up here and there, working to overthrow Nightmare Moons new regime, for better or worse. There are many various reasons why these ponies rebel, but they have all come together under the blanket term of 'Equestrian Loyalist'. They desperately strike out against the New Lunar Empire in the hopes of restoring their beloved Equestria to its former glory.
Their job is not an easy one, however. Many look at the freedom fighters as mere terrorist, stirring up trouble simply because they cannot let go of what once was. Many blame the Loyalist for disturbing the new found peace an prosperity found within the darkness of the night. The Loyalist denounce these neigh sayers as cowards and complacent slaves to their new dictator. In the end, who can really say what is right and what is wrong?
The only thing you can do is believe in your own heart as you walk down an uncertain path.