Excerpt taken from Professor Julian Orsini of Londinium's text The Roman Far East.
"When discussing the Roman conquest of Persia, it is criminal to not deviate slightly and discuss the two Ursinaic Empires. Though the second is better known and had more of an effect on our own history, the first is equally as important.
The First Ursinaic Empire was one of the most unique states ever built by mankind, not just for its idiosyncratic political system and early treatment of men and women as equal, but for the animals it was based on: the Semetic and Germanic Urs.*
An oddity, especially considering that the Caucasus was on of the first places to adopt the horse, but most historians agree that a plague killed off the horse population in the mountains, and the local tribes, who were Germanic in origin, responded by domesticating the Germanic Urs north of the main ridge and the Semetic Urs in the southern area approximately 2000 years before the founding of Rome.
Little is known about the history of this area until a minor Greek chronicler, Acacius wrote about it around 30 years before the founding of Rome, however that document has controversial due to the early year of its writing.
The first real account of the Ursinaic cultures comes from an Ursinaic scholar, Jokhas of Kierk, during the reign of the First Empress, Amelei I (Reigned 28-41 AUC). In Jokhas' document, he described the two cultures that existed prior to the founding of the Empire. The 'Ursine Kraig' and the 'Kaiokylader Ryekyas.' The Ursine Kraig, a horde-like state under the rule of the Iron Ryek, was by far the dominant of these states, using the Germanic variant of the Urs, and in 22 AUC, embarked on a set of conquests of the southern city-states, which had adopted a more Persian culture through minor amounts of trade and used the Semetic Urs for farming and food.
By 28 AUC, Amelei I had united the Kaiokylader Ryekyas under the rule of the Ursine Horde and declared herself Iron Ryeka of the Kraig and the Kaiokyladers, a title approximately equal to Emperor in terms of authority.
Throughout the ensuing years, Amelei's successors conquered the entire Caucasus region for the Empire using their Urs forces, reaching the largest extent under Ryeka Natakha II, the Golden Empress in 251 AUC. After Natakha II's death, the Empire began to rapidly contract and break apart, eventually splitting into the Six Ursine Kingdoms by 300 AUC. However, their successful use of the Urs in warfare and farming later led to a resurgence under Ryeka Kanthel I, the Iron Queen, who created the Second Empire in 381 AUC."
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*The Syrian and Eurasian Brown Bears, OTL
So, in summary, a Germanic Empire in the Caucasus using Bears instead of Horses after a plague wiped out the horse population in the Caucasus in the 3000s BC, causing the Brown Bear to be domesticated. Rome still comes into being (though differently), as the culture has very little interaction with the outside world before the Empire is created.
The map itself shows the preceding states in 21 AUC and the Empire at it's greatest extent in 251 AUC.
