Equestria

Equestria is the homeworld of Twilight Sparkle, Rainbow Dash, Pinkie Pie, Rarity, Applejack, Fluttershy, Spike, Princess Celestia, and Princess Luna. Equestria's only sentient inhabitants are mainly ponies, unicorns, and pegasi. It's peaceful, pretty, and colorful. It has a very rich history, it's under the heroic protection of Twilight and her friends, and is ruled by Princess Celestia, the sun princess, and Princess Luna, the reformed moon princess.

Origin
Sometime before the series' events, The three tribes: Earth ponies, unicorns, and pegasi did not live in harmony. Each of the three tribes didn't care for whatever troubled the other two, but only for their own welfare. The Pegasi controlled the weather in exchange for food from the earth ponies. The unicorns were in charge of controlling day and night in exchange for the same thing. But mistrust between the tribes increased until a mysterious blizzard overtook their land. Each group of ponies decided to find a new place to live, but they all arrived at the same new place, but the blizzard followed them. The ponies figured out there was only one way to get rid of the blizzard, to treat one another warmly. The unicorns used magic to build Canterlot and once the city was finished, they invited the pegasi and ponies to a party, which became a yearly event called the Grand Galloping Gala.

Discord's Reign
Before Princess Celestia and Princess Luna ruled Equestria, a terrible and powerful multi-crossed creature named Discord ruled it causing nothing but chaos and disharmony. However, Celestia and Luna found the Elements of Harmony and used it to turn Discord into stone, and stopping all the disharmony of Equestria

Nightmare Moon's Reign
After Discord's defeat, Princess Celestia and Princess Luna ruled over Equestria to take the unicorn's place as controllers of the sun and moon and maintain harmony after Discord's defeat. However, the three tribes disliked the night, which made Luna grow bitter, and she eventually refused to lower the moon to make way for the dawn. And soon, Luna's bitterness transformed her into the evil Nightmare Moon. Celestia reluctantly harnessed the power of the Elements of Harmony again and banished her inside the moon, taking responsibility for both sun and moon, maintaining harmony in Equestria.

Nightmare Moon's Return
Thousands of years later, Nightmare Moon returns due to the power of the stars, and plans to declare eternal night. However, Celestia's top student, Twilight Sparkle, along with her new friends, planned to stop Nightmare Moon. Twilight finds the Elements of Harmony, but Nightmare Moon destroys them. But Twilight and her friends, having represented the 6 Elements of Harmony during their journey to defeat Nightmare Moon, becom the NEW Elements of Harmony, and as a result, defeat Nightmare Moon and restore her back to Luna. Celestia gives Luna another chance to redeem herself of her ways, and Equestria is back in peace.

Discord's Return
Over time, Discord is freed from his stone-cold prison, and goes back to bringing chaos in Equestria. Twilight and her friends were Equestria's only hope since they now represented the Elements of Harmony. However, Discord, having used the groups' powers against them, manages to corrupt them into being cruel and careless. But Twilight soon gains her power back, and revives her friends from their cruelty, and with their powers back, they defeat Discord together, once again turning him to stone.