Shiwan

The Shiwan are loyal vassals of the Emperor, but their history runs older, deeper, and are ancient family and staunch allies of their brothers and sisters in the Bayushi clan, for whom they share the same language and faith.
Defeated in an old war by an old emperor after bending the knee, they have not abandoned that which they take pride in.
The Shiwan might have been legended as farmers, had they wanted to. Their fields were more fertile, their crops and cows and pigs more than any other, their rivers bountiful. But this is not what they take pride it.
They may not have the best equipment, the best magicians, or even the strongest men.
But Shiwan take pride in their numbers.
Their population is vast, some say more than many of the other Vassals combined.
Their armies make the ground quake on its march, that they drink rivers and ponds dry, and arrows blot the sun when they fight.
All men are pressed into service for the Emperor, and fielded into Shiwan legions, the only type of army of its kind in the entire Empire. In addition to numbers, they are also known as expert organizers and logisticians, for they need to be such that they hold the reigns on the greatest and massive fighting force the Island has ever seen.
The military backbone of the Emperor, where as the Karasuba can be described as his cloak and dagger, the Shiwan for providing their numbers have earned the monicker: the Emperor's sledgehammer.
In the domestic ground, most civilians are farmers, the rest being managers, accountants, and organizers. Women and families who give birth to many children gain a high status in life, and it is part of government regulation that all families who contribute a number of men to the army gain privileges, extra wages, and the ability to support more men. Polygamy is encouraged, and some families who have given birth and raised some dozens of men have rose from farmers to aristocrats in a stroke.
The same can be said for the barren and the single. Singlemen and women are scrutinized, and law dictates that after a certain age they be mandatorily paired up. Barren women are particularly out of luck, and almost shunned from all society. However barren men may become Eunuchs, and go to schools to serve as advisors and management of many.
Thus, quite a lot of the educated and organizing class are eunuchs.