Truebloods do not regard anyone as their equals. To them, we are just animals, barely worthy of living. And to them, killing an animal is no crime. I was in Kyziania in 4999, when they sacrificed more than 30.000 slaves in a week. It has been 34 years, and I can still hear the constant screaming every time I close my eyes.While the Kyzian Empire has existed since what seems to be forever, it only began expansion beyond the desert of it's birth about 2000 years ago. Until then, the Trueblood rulers had seemed happy and content with what they had.
It is not common knowledge what prompted the former dragon servitors' aggressive stance, but it happened. Around the year 3900, the dragonborn went to war.
Fairly quickly, although without rush, they subjugated all kingdoms and citystates on the northern part of the continent. For years, the Kyzian empire was unopposed in it's conquest, until it's armies ran into the lands and armies of Varnor and Ortygal, down to the south and the armies of what is now the Cursed Lands, to the north.
In the north, the dragonborn were stopped, but the Kyzian empire took a lot of land from Varnor and especially from Ortygal through many years of war, although the costs ran very high. Eventually the dragonborn stopped their expansion and reached a tentative peace with their neighbors.
Of course, said peace didn't last long. Now, so many years later, much has changed, yet some things remain the same. While there has been no real war between the empires for many years, small and large skirmishes between the Kyzian empire, Varnor and Ortygal are fairly common. Most generations of soldiers get to see some action. Some more than other.
Just like with their wars, the dragonborn of the Kyzian empire seem stuck in a perpetual state that never changes. For millennia, the empire has been run by the Truebloods, those dragonborn who can trace their ancestry directly back to Kyz, the first dragonborn created by the dragons. If you are not a Trueblood, you can never have a position of real power in Kyzian society.
But the caste system doesn't stop there.
Following the Truebloods are the rest of the dragonborn in tier two. The dragonborn are free "men" and allowed to pursue any vocation in life, but most are used in the army, as soldiers. If they are exceptional, they might receive a position of trust, but never of power.
Below the dragonborn, in tier three, you will find the Sunites. Sunites born in the Kyzian empire are slaves, but mostly treated well, and a few are given their freedom. Obviously, as a slave, you can end up anywhere, but in the Kyzian empire, most Sunites are given positions that suit them. They are often used as teachers or for other light (indoor) work, if they have any aptitude for it. Visiting Sunites are not automatically slaves, and will most of the time be able to walk the streets without fear of being thrown in jail or accosted by dragonborns.
The fourth caste is made up by all the other races. Elves, dwarves, gnomes, etc. There aren't many left nowadays, as the Truebloods are not overly fond of them, and have been trying to eradicate them for many, many years. All are slaves, with no possibility of ever being free. If you are of one of the other races and visit the Kyzian empire, you better have a signed statement from a Trueblood that you are to be left alone, unless you want to spend the rest of your life as a slave, working the many fields of the empire.
At the bottom of it all, in the last tier are the Moonites. Barely perceived as more than animals, all Moonites are slaves, slaves that spend their time in chains. A moonite walking around alone, without a slave necklace, is killed on sight. Even the necklace does not always protect a slave out on his own.
As you might surmised, slavery a part of daily life in the Kyzian empire, and there are a lot of them. In fact, almost one third of all inhabitants of the empire is a slave. It is said that more than 1 million slaves enter the capital Kyziania every year. Many are just sold there and shipped elsewhere, but a great many are used there to make the city run smoothly, although a not insignificant portion lose their life on top of the Truebloods' pyramids in their ancient and bloody worship of Nira.