The founders of the Equestrian Monarchy were King Helios and Queen Nocturne. After the two alicorns revealed their presence to the warring four tribes (Earth ponies, Crystal Ponies, Pegasi, and Unicorns), they showed the four tribes the concepts such as unity. You know how this story goes, the four tribes all agree and stop fighting and the Windigoes are banished by the power of friendship.

Many years wear on, Canterlot itself is founded by the two alicorns of the Sun and the Moon. Many Equestrian things one can see today are constructed, such as the groundwork for the nationality itself. Although back then, it was a lot smaller. There were other pony tribes beyond Equestria, who were not convinced of the beliefs that the Equestrians had. Among other races were the dragons, rams, griffons, seaponies, centaurs, (who never had any relation with the four tribes), deer, and various other races.

Eventually Equestria had a stable society, and the racial tensions between the four races had largely vanished. This was around 300 years after the founding of Equestria, and it took much trial and error. The King and Queen were revered by the populace, yet they were humble and generally wise. Equestria was stable, and united. 

That was until the dark, tyrannical ram known as Grogar would come to power over the rams, ruling over the nation of Ramhorn from the capitol of Tambelon. Grogar's family were murdered at a young age by evil ponies, and this broke his friendship with Starswirl the Bearded. The two of them were once best friends, one could say brothers. The two of them studied under their master, a dragon known as Melcade. Melcade taught them all various kinds of magic, geometry, physics, the whole works. 

The two of them planted opposite seeds, one of harmony, and the other of disharmony. This would lay the ground to the Ramhorn-Equestrian war, which resulted in a massive conflict where the Rams had stormed through Equestria and had appeared to have the upperhand. 

Grogar's dark ways had tempted the crystal ponies into switching sides and betraying Equestria. Their leader, Sombra, was a well renowned and revered scientist who was tempted by Grogar's dark ways years prior, who offered him much knowledge into the dark arts. In secret, Grogar would teach Sombra all of his abilities, and ascended him into Alicornhood in a series of dark rituals. 

When the time was right, Sombra revealed his true colors, and violently overthrew the leadership of the Equestrians over the crystal ponies, forging the Crystal Empire, when it seceded from the Equestrians the Crystal Empire declared their alliance with the Ramhorn Imperium and together, the two forces converged on Equestria. 

Starswirl himself would duel Grogar after he had successfully defeated the King and Queen using the power of dark magic (though he didn't have time to kill them as he wished), and using the elements of harmony (which Starswirl created), Grogar would be defeated and banished into the stars, becoming a constellation. After Grogar was banished, his armies were all scattered to the winds and surrendered, withdrawing themselves back into Ramhorn.

After Sombra was aware of the defeat of his master, Sombra would surrender and make a truce with the Equestrian Monarchs, that he would withdraw into Crystal Pony lands and not make any further actions against Equestria in the future. After the brutal conflict, they were forced into accepting this, and his armies would withdraw into the Crystal Empire.

The King and Queen would be able to recover from the dark magic, although their lives were very much shortened by this affair. Thankfully they had two young fillies, Celestia and Luna. 5 years after the conflict ended, they would give up their power to Celestia and Luna, after which the two of them would pass away. Starswirl would teach the two sisters about magic, and do his best to groom them to eventually be Equestria's monarchs.

After the war had ended, the Imperium of Ramhorn would eventually collapse into infighting and civil war, and be carved up by the various nations around it, effectively ending any semblance of Grogar's rule, and in the carving up of Ramhorn, the Equestrians had managed to gain Tambelon itself. The Rams were not very fond of this, and would often have rebellions and uprisings, all of which would be put down. Perhaps one could say this was revenge for the war itself. 

As the years wore on after the Ramhorn-Equestrian war, Celestia and Luna would grow to become capable leaders in their own right. Starswirl would pass away at a very advanced age, leaving behind a mass range of magical spells and studies for those to follow in his name. Starswirl's advanced understanding of magic, and intentions for it to only be used for good was made most clear, and Equestria would open up a university dedicated to studying magic in his name.

Equestria would experience two centuries of peacetime, and would grow to become even more influential in the world. With the affairs with the rams eventually settling down, granting them Equal rights around a century after the war had ended, would finally quash ram resistance to the Equestrian crown, and the Rams would assimilate into Equestrian society. Other races, such as the Dragons and Deer had Ram lands as well, and at the time, Equestria had treated the rams better than they did, so most Rams would end up assimilating into Equestrian society.

As such, the two sisters maintained balance for their kingdom and all their subjects, the earth ponies, pegasi, rams and unicorns. Not only that but they protected them from many dangerous foes. Monsters, tyrants and brutes, all who would have no doubt destroyed Equestria and plunge it into chaos and despair, were all brought down thanks to their unity.

But as time went on, the eldest sister grew fearful. For every foe the sisters faced, she worried that a new more powerful one would appear out of the shadows and the two would not be able to stop it. She was convinced only in the light of her day that they could perceive an upcoming threat. So one fateful day, the paranoid elder Alicorn refused to lower the sun to make way for the darkness of night, convinced it was the only way to forever save the kingdom from danger. The younger sister tried to reason with her, saying that the balance between day and night must be kept but the fear in the elder one's heart corrupted her into believing that she alone must rule Equestria and safeguard it. From this hubris she transformed her into a wicked mare of flame: Coronal Flare.

She vowed that she would cover the land in eternal day, for no enemy could hide in the light. Reluctantly, the younger sister harnessed the most powerful magic known to ponydom: the Elements of Harmony. Using the magic of the Elements of Harmony, she defeated her elder sister, and banished her permanently in the sun. The younger sister took on responsibility for both the moon and the sun, a heavy burden to bear on her body as well as her soul, but the balance of peace and harmony was maintain in Equestria ever since.

Timeline (vague):

2000 BCS (Before Current State) - Four tribes unify under Queen Nocturne and King Helios.
1800 BCS - Founding of Canterlot.
1700 BCS - Ceasing of racial hostilities between the three tribes and integration of all tribes into one unit.
1500 BCS - Grogar takes power over the Ramhorn Imperium.
1567 BCS - Grogar begins the invasion of Equestria, starting the Equestrian - Ramhorn war.
1566 BCS - Ramhorn armies march on Canterlot in a successful seizure of the city.
1565 BCS - Sombra overthrows Equestrian leadership, the Crystal Empire itself is founded. 
1563 BCS - Grogar is defeated and banished into the stars as the Constellation Ares.
1562 BCS - Sombra surrenders conditionally to Equestria, and his forces withdraw into the Crystal Empire.
1557 BCS - King Helios and Queen Nocturne pass away, leaving Starswirl in charge as he finishes raising the two sisters and teaching them how to rule and perform magic, as well as to use the elements of harmony.
1550 BCS - Imperium of Ramhorn collapses into civil war and is split by neighboring forces. Equestria seizes Tambelon.
1531 BCS - Starswirl dies peacefully in his sleep. Celestia and Luna officially become the rulers of Equestria.
1463 BCS - Equestrians grant rams equal rights and Rams assimilate into Equestrian society.
1200 BCS - Two centuries of peace and prosperity.
1180 BCS - Lord Tirek invades Equestria with the intentions of absorbing all magic for his selfish interests and is defeated, and banished into the Moon.
1120 BCS - Border hostilities with the Crystal Empire erupt into all out war with a peace treaty signed later that year that reverts the two nations back to their previous borders.
1100 BCS - Invention of Airships in Equestria.
1000 BCS - Celestia transforms into Coronal Flare. Equestria is divided East and West, with the East being the loyalists under Princess Luna, and the West being the rebels under Coronal Flare. Beginning of the Equestrian Civil War.
998  BCS - The brutal civil war ends with Coronal Flare being banished into the sun, her followers and armies exile themselves from Equestria, the civil war ends.
997  BCS - Luna becomes Queen of Equestria, assuming the name Lunara and wields the elements of harmony.
 

----

Am looking for people who are skilled with this sort of thing. Could potentially use this for an RP or fanfic at some point but as of right now, I am wondering if anyone can take a look at this and see if there is anything that can be improved upon. 

Perhaps @Blitz Boom @Illiad Easle can take a look at this?