[@Tangletail]
Glad you asked! I was working on getting this into the Atlas, but it'd be something every character knows. This is going to be a bit of an info dump guys! Sorry about that but I'll split it up into sections so it's easier to digest. The current year is 138 in the Age of Owls. The Age of Owls began after "The War of Splitting Branches" a world war that completely uprooted how Ithea was divided up politically and magically. So it's been around 138 years since the war. In this world there aren't any super long life spans. Wood-Elves have the longest typically living to around 100. 

[hider=The Embers of War]
The high-elf nation of Ellvenaan ruled portion of Carthus. For decades warring human tribes and broken kingdoms were under the rule of the high-elves. Viguard (which was made up of both Ostguard and Viguard at this time) was fearful of encroaching annexation. High elves had learned to use their magic to tame dragons, and not even Bjorn could withstand dragon fire. 

The elves also had their thumb on most of Valenndale, but humans here adapted to the mercantile arrangement through developing innovations in trade and commerce that made them more useful to the elves as partners rather than slaves. They were nonetheless considered colonies. 

In Penault, Le Feu Mot, one of the most advanced human civilizations for its time had rebelled against their encroaching elven colonizers. The Otmonguard instead remained neutral and isolationist though for reasons unbeknownst to most the high elves didn't attack or ally with the Otmon. Penault was handily defeated, but their rebellion ignited a passion throughout Ithea. See, Penault had done something that no one thought possible. In the 'Battle of Brittle Sands' they killed one of the elven dread dragons, Sepirat the Aged. 

Meanwhile the Brith had carved out large chunks of High Mist (though regarded Tiefling territory as a waste, and Gnomish territory as more reliable as an independent but controlled entity). The Brith had access to slaves from the Fleeting Isles and soldiers from the Orc tribes spread throughout. While they didn't have the feared dragons of legend like the Elves they were incredible naval warriors. 
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[hider=Alliances Forged]
Hearing of Le Feu Mot's success in slaying a dragon the Viguard Empire began to take the steps necessary to building a resistance- specifically Lord Magnate (Dwarven King) Siegfried and his military adviser and sister Bridgette. They began a propaganda campaign that invigorated the Dwarven fears of magic and the elves. While the campaign stoked a fierce nationalism it wasn't until Titus Chamberhill arrived in secret to Bjorn with an envoy to properly form an alliance. Chamberhill could trace his ancestry back to kings of old before Elven conquerors has taken Carthus. He too had worked to unify the human tribes, villages, and entities that were scattered throughout the continent. He tried to seek aid from the human colonies in Valenndale but his requests were left unanswered. 

Unified under a common goal, to drive out the elves, Siegfried, Bridgette and Titus worked to subtly undermine elven legitimacy and power in the region (spying, subterfuge, allying with wood elves, training human mages with elven tactics, etc.) It wasn't incredibly long before Ellvenaan took notice and arranged a treaty. The leaders of the resistance were invited, along with the leaders of Britheria, to the Great Summit to form an armistice until a treaty could come about. 

Not much is recorded or at least readily available regarding what actually happened at the Summit, but negotiations didn't go well. It was here that Siegfried, Bridgette and Titus found themselves facing off against Armatta the Sage another of the elven dragons. It isn't known how they survived, but this was the beginning of war. 
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This has been an overwhelming amount of info so far. I'm sorry about that! I'll sum up some of the major events in the war though so this doesn't go on forever. 

[hider= WOSB Some Main Events]
> The Elves ally themselves with the Brith recognizing their vastly superior naval potential. The elves had lost two dragons at this point, and were facing two of the most heavily populated races in Ithea. They concluded that Orcish hordes would destroy the resistance's ground forces, and thus sought out help from the Brith in return for continued dominance in High Mist and most of Penault when the war was won. Orcs were promised freedom by the Brith in exchange for their assistance. 

> The humans and dwarves formally named their resistance the 'Iron Alliance' 

>For the first year there were major defeats to the Iron Alliance in what is Astoria today. Every town and village was blockaded by Brith fleets, and Orcish foot soldiers easily defeated the soldiers. 

>The Elven dragon Deis the Conqueror (the largest dragon of all) destroyed an entire city (now known simply as Ashenfield, a minor noble's estate) to show demonstrate its might. Dragons throughout Vicelles and Astoria burned cattle and crops (with elven saboteurs salting the fields) to force surrender. 

>The first ballista was created by Dwarven inventor Draka ba Clindor and built into the architecture in Bjorn and other dwarven cities. 

>Mages were soon forced by law to join the burgeoning Military Academy to train them in magic combat. Those who didn't were branded as traitors and apostates by the Iron Alliance. 

>Human armies used feral vampires and werewolves in the 'Battle at Orlok' against Orcish hordes. This battle was the first step in the Orcs abandoning the Brith and Elven alliance. 


> [color=0054a6][b]Ardent Fair of The Bog[/b][/color] held the line in what is Ardent's Fall today. She and her mages held off and killed three dragons in three nights of Elven attack on the city. Ardent died killing the final dragon, Deis the Conqueror (the largest of any elven dragon). 

> Upon learning of the incoming Brith fleets to capture Lubck (the most prosperous city in the Dwarven Empire) Siegfried somehow came to learn of a dark magic capable of poisoning the Iron Ocean. He used this to destroy the incoming Fleets which tremendously weakened the Brith forces, but the magic ate away at parts of his cities as ocean water completely engulfed two districts. Siegfried would take his own life that same night. 

> For unknown reasons the Ellvenaani forces began losing control of their Dragons. Many dragons either died out or went insane, but were lost to the elves all the same. 

> Seeing the war was lost the Orcs massacred Brith nobles and occupying forces overnight, and this forced many of the Brith to retreat back to their homelands in Crysteria. 

>The repair efforts were incredibly costly for Carthus as this is where most of the war took place. This is how many of the noble houses came into power in Vicelles. The wealthier powers sought to create a nation separate from the Chamberhill dynasty. Viguard soon split into two after the power vacuum that was created by Siegfried's death. It was messy, and there are still growing pains, but the nations have become very prosperous in the last 100 years.  
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