The Overthrow Theory

In 'My Little Pony: Friendship is Magic' fandom, it is constantly joked that Princess Celestia is foreseen as a 'troll' or just someone who is mischievous or otherwise evil in personality. However, could this all be actually true about her, and contain hidden secrets in the world of Equestria?

As we could see and theorize in 'Magical Mystery Cure', because of her understanding of friendship and the creation of the spell that Star Swirl the Bearded could not accomplish, Twilight Sparkle was elevated to godhood as an alicorn. How did this happen? It appeared that she was killed by her friends by being blasted by 5 lasers that protruded through their necklaces. This had me wonder how Princess Celestia and Princess Luna could have become alicorns, as well as Princess Cadence. It could just be the case of 'born into royalty', but as shown in the chapter book 'Twilight Sparkle and the Crystal Heart Spell', Princess Cadence was elevated as an alicorn after defeating Prismia, via her own necklace. The power from the necklace could have most likely killed herself, taking to the 'afterlife' where Princess Celestia was. This only makes me wonder how Celestia could have acutally become a alicorn and was put into the throne. Here is what I and a friend come up with:

Celestia's and Luna's parents, lets call them 'Princess Solaglow' and 'Prince Midnight', were both the rightful king and queen (or prince and princess) of the kingdom; Solaglow with the power of the sun, and Midnight with the power of the moon. Both had their children named Celestia and Luna, and the children's childhoods were lovely and great, but this all changed when Luna had obtained her cutie mark, the ability to control the moon and other celestial entities just like her father.

Celestia was thrown into a fit of jealousy from Luna's so soon cutie mark, and in turn had used her own powers to throw her into the moon, killing Luna. Princess Solaglow was put into a state of fear that Celestia, with such power, could easily overthrow her and Prince Midnight. In an act of retaliation days later, Princess Solaglow sent Celestia into the sun. Unknown to either member, Celesia had lived and had reincarnated as a alicorn. Celestia, while living on the sun, had obtained her cutie mark and realized her special ability was to also control the sun and other celestial entities. Months, or years later, Celestia had returned to Equestria and killed both of her parents, in which only alicorns can kill alicorns. Celestia had sealed her parents powers in a gem, known now as the "Alicorn Amulet", and locked it away in a vault, until one day it vanished after a thief dressed as a guard sneaked into it and sold it to the black market.

Celestia was able to brainwash all peasants and residents of Equestria that she was the true princess of the land using her own magic, making her now known as Princess Celestia. She put up a back up story for what had happened to Luna, which is seen in the beginning in the first episode of FiM.

Celestia knew that if she had died and was able to live on the sun, then her sister would also had become an alicorn and lived on the moon, making her able to return to Equestria and possibly overthrow Celestia. Celestia did not worry about this, though, for she had another idea up her sleeve.

During her time in Canterlot, she searched for a unicorn that had the potential to be her successor if she were ever killed. This successor? Twilight Sparkle. She was able to see that her talent was to easily manipulate magic, and if so could fulfill the story about the Elements of Harmony. She trained her in magic, allowed her to reside at Canterlot's Library, and by the time she felt Luna was about to return, she sent Twilight into Ponyville to quickly gather the elements and discover friendship. When the day had come for Nightmare Moon, Princess Luna's physical form of anger towards her sister killing her and the idea to take back Equestia under her rule, Twilight and her friends were able to weaken Luna by wiping over her mind with the idea that the events of what happened in the story book is what she had done, and also reversed her age into how she looked before she died, only still regaining her alicorn form.

Princess Luna was able to find out how to bring her true age with an aging spell, but with the affects of the memory wipe, never bothered to really find out what happened to her.

As Twilight's adventures in Ponyville continued, she learned more and more about the power of friendship, and was finally elevated to godhood as an alicorn. So now, Princess Celestia will be able to teach Twilight how to be a successful ruler if anything were to happen to her. This may backfire, however, if Twilight finds out the true story behind Equestria and stops Princess Celestia from ruling.

This, however, is very unlikely as there is no proof given in Equestria that Princess Celestia had done all of this.

Other main villains in the series can show how corrupt Celestia is as well:

Discord could have once been Celestia's pet, and after Celestia's overthrow of her parents, Discord wanted a kingdom of his own. Discord went after a nearby town, but was quickly stopped by Princess Celestia for she did not want any other kingdoms to interfere with her own. She put him in a stone prison, and left him in a garden. The events of 'Return of Harmony' show that he had tried to do this again, this time by taking over Ponyville, but with no avail and was put in a stone prison again. In 'Keep Calm and Flutter On', Princess Celestia had an idea to spread her rule by using the power of Discord, and so with him reformed, she would be able to use his powers to spread her kingdom across the entire planet, and maybe even another planet.

The Changelings could have been pets of or friends of the late Princess Solaglow and Prince Midnight, but after Princess Celestia overthrew them, they could have attempted to take back the kingdom for their friends, but had failed for Celestia was able to convince her people that the Changelings were dangerous and should be destroyed no matter what. They escaped, and they since then planned for their revenge against the Equestrian Kingdom. Their lack of food, known as love, forced them to put the plan in for both revenge and for food in the episode 'A Canterlot Wedding', conveniently allowing then to attack as the elements of love would be brought together, giving them an endless source.

Prince Sombre was attempting to become an alicorn by himself by searching for a way other than dying, this and take over Celestia's kingdom, but this came as a failure and he had died without becoming an alicorn. In 'The Crystal Empire', his ghost returned to resume what he had attempted to do and take over the land of Equestria without worrying about becoming a alicorn for he was already an unstoppable ever-living being. This, again, came to no avail and his soul was trapped within his horn, awaiting a body for him to take over and start all over again. This possible being he could have possessed? Derpy Hooves. Just note she was absent throughout most of Season Three, only appearing in a few episodes, until finally making some large cameos in 'Magical Mystery Cure'. But this is a completely different theory by itself, and almost connects to nothing with Celestia.

Celestia being evil can also be hinted by Faust attempting to call Princess Celestia "Queen Celestia", but Hasbro brought this down saying that in these times queens are looked at in fairy tales and other stories as being evil.

All hail Queen Celestia, may here light shine upon us and guide us to a brighter future.