A pony may live their entire life without giving a thought to the bodies that govern them, that shape and enforce the laws that they follow, that hold the peace against outside threats. I am not one of these ponies, and you shouldn't be, either. After all, isn't it just a bit prudent to understand the system you live in? Let me educate you with my first published report on politics: specifically, the aristocracy.

Headcanons abound, but this is all based on what we've seen in the show. It's not complex (intentionally), and I hope it's not boring, either. OC tag is for the unnamed author.

Between the banishment of Nightmare Moon and her revival as Luna, Equestria was blessed with one thousand years of prosperity under Princess Celestia. There are some historians today who call it "The Dawn Age", though it ended only recently. And yet, for a small group of ponies hidden far from other civilizations, Celestia's golden age was anything but.
Luna's Children of the Night were originally a group of twelve foals whom she rescued from poverty and starvation. She whisked them away in the night to serve as the founders of a new colony - one for which, eventually, she was punished. Still, even after her banishment, her Children lived on, tucked away in mountain ranges far beyond the sight of the sun.
So, over the years, what became of these children?

Based on the MLP fan animation Children of the Night, which can be found here.

Sure, Rainbow brushed up on her history, but she never expected to be taking an oath to enter the Wonderbolts. What's this about battles?

The Monster Defense Force long protected Equestria from the things that go bump in the night. So why does it not exist in the modern day? How did it end, and where are its employees now? Most of all, where does a bulldog fit in? All these questions and more will be answered!

Daring Do, as most ponies knew, was a legendary adventurer-archeologist who spent her life going to places no sane pony would and recovering artifacts of immense power, all the while combating her archnemesis Ahuizotl and his seemingly endless legions of minions. Everypony also knew that her best-selling books were written by the mysterious, reclusive author named A.K. Yearling. The part nopony knew was that they were, in fact, one and the same pony - and very real.
Therefore, nopony felt bad about making their own additions to the ongoing, increasingly exciting but convoluted storyline. These stories would get posted on fan-based websites (the concepts of "computers" and "Internet" were quickly catching on), where fans would read, rate, review, and write. Daring Do was, at best, mildly aware of this "fanfiction", as it was called. She'd certainly never read any of it.
When she found a free day and decided to check it out, little did she know what she would find...

Rated only for reference to things, but nothing is shown in any detail whatsoever.

Spitfire and Soarin have always been the best of friends. Neither of them expected their first Wonderbolts show to change the course of their lives forever.
Somewhat implied Soarin/Spitfire.

Scootaloo is known for being a fervent admirer of Rainbow Dash, a member of the Cutie Mark Crusaders, and being wickedly fast on her scooter. But one question remains on everyone's minds when they think of her: where is her family?
Well, who better to ask than Scootaloo herself?

Warning: Contains character death (no gore).

Fluffy pink cotton candy clouds have appeared across the land. Most would not feel threatened by this, but it's been happening for days. The unicorns have been blamed for their magical tinkering of the weather, but they are not responsible. So, who is? That's what three unicorns have been sent to find out. But the truth may be even worse than they expected...

Warning: Contains character death (no gore).

This is a mere glimpse into Celestia's past, present, and future. When you are immortal, you know that you will eventually see your closest friends die; and nopony knows this better than she.