Tevinter

The Tevinter Imperium is the oldest extant human nation in Thedas and is ruled by a powerful magocracy. The leaders of the Imperium are called magisters, and are led by the Imperial Archon. In ancient times, the Imperium's power was unrivaled and its borders stretched across nearly the entire continent. In modern times, while Tevinter is a shadow of its former self in both size and power, it is still relatively powerful, and a major nation of Thedas.

The land was at first ruled by a dynasty of kings. Circles of Magi formed in Tevinter cities as closed societies of mages, presumably to train and study their talents. They formed a council of their most talented mages, the Court of Magisters, which convened in Minrathous and decided the mandate of magic in the kingdom. In -1195 Ancient, the premier magister lord, Archon Darinius, took power as its first Archon and founded the Imperium, establishing the magisters as its aristocracy. Darinius was the first human to successfully ally with the dwarves of Kal-Sharok and traded extensively with them.

The Archon Thalsian, one of the first magisters, claimed to have contacted the Old God Dumat to learn blood magic, which he used to declare himself the ruler of an empire. Thalsian established temples to worship dragons, which became a symbol of power within the Imperium. He created the "Altus" as the ruling class, also known as "The Magisters", while his pupils formed the noble houses that ruled the empire for millennia. The Imperium declared war on the elves in 214 TE, marching into the Arlathan forest to lay siege to the city with--it is said--demons and dragon thralls. Six years later, the magisters and then-Archon Thalasian sank the city into the ground with blood magic. Elven survivors were enslaved, despite their talent for magic, and from them, the magisters learned to use lyrium to enter the Fade.
Tevinter society is notoriously decadent yet also takes great pride in their history and culture, as indicated in that everything they've built has been carefully preserved and renovated. Ambition and magical ability are the hallmarks of its ruling elite, the magisters. Though blood magic is now banned in the Imperium, mages who practice it are quietly acknowledged as the most proficient dreamers and diviners. This circumvention is often necessary in order to simply survive the deadly rivalries and competitions for power and influence amongst the Tevinter noble families.The well-bred altus sneer at the laetans, who in turn sneer at the praeteri. They vie for dominance in the Magisterium, where factions shift and flow on a daily basis with deadly consequences. Then there are the so-called soporati, the "sleepers." These are the non-magical citizens who vastly outnumber the mages, yet are beholden to their whims. Many are resentful of this status, plotting in secret, even as they secretly hope their children will possess magical talent. It has an enormous merchant class, enough teeming poor to drown any other nation in Thedas, and the shadowy thieves called "praesumptor".

And then there are the slaves. One would think they, at least, see each other as equals, but it is not so. The divide between the freed liberati, those who act as personal servants to magisters, those who work on farms and factories, and the "servus publicus" who do all the tasks proper citizens will not—it is all but insurmountable, but perhaps in emulation of those who own them, Imperial slaves will connive and scheme to try anyhow. Outsiders might see it as futile, but to Tevinter citizens, their nation's social classes are the most mutable and rewarding of merit in all of Thedas.