Unless stated otherwise, all information herein is taken from The World of Robert Jordan's "The Wheel of Time", Chapter 17.
Seanchan is an Empire, usually ruled by an Empress, although males can become emperor (TGH, Ch. 34), the last to do so was Algwyn, nine hundred years earlier (WH, Ch. 14). When the return began, the Empress was Radhanan, a widow (CoT, Ch. 10), with several surviving children (KoD, Ch. 11), though Tuon was her favourite and had been named, though not proclaimed, heir (WH, Ch. 14). With the murder of Radhanan by Semirhage, Tuon is now Empress, with the new name Fortuona, though the Empire in Seanchan is in chaos (This passage needs a reference).
The Seanchan empire has a complex class structure. At the top is the Empress and then the Imperial Family, under which is the nobility, the Blood, divided into the High blood and the Low Blood (WH, Ch. 21), with two levels of each of these (TGS, Glossary). Originally, these were descendants of the nobles that accompanied Luthair, but it is possible for commoners to have their name added to the Blood and to become nobility, or for nobles to be adopted into the Imperial family (TPoD, Ch. 24).
Under the blood, are commoners with slaves, da'covale, typically occupying the lowest rung of the ladder. so'jhin are da'covale, but do not fit entirely within the structure, as the so'jhin of the blood are considered of higher rank than commoners, and so'jhin of the high blood, or imperial family are often considered of higher rank than the low blood. Seanchan people do not meet the eyes of those of higher rank than them, and if the difference is great, they will not even look directly into their faces.
To mark their station, Seanchan nobles shave parts of their head and laquer their fingernails. This is such a significant designator of rank, that baldness is not publicly displayed and those that lose their hair are required to cover their head. Members of the blood shave the sides of their head and those of the imperial family, though not the high blood, their whole head. Those of low blood may not be entitled to shave their head at all, and will have to rely on laquered fingernails to denote rank (TPoD, Ch. 24). Egeanin shaved her head all the way round above the ears, leaving a bowl shaped hairsyle above it (WH, Ch. 19). So'jhin may also have the sides of their head shaved, depending on role and rank.
All nobles will have long fingernails, and the low blood will lacquer the little finger. The high blood will lacquer the ring finger also, while members of the imperial family will additionally lacquer their middle finger. The Emperor/Emporess will lacquer all five nails.
Being an independent country, Seanchan does not have to trade with foreigners. In fact, the Sea Folk, being the only ones able to because of their seafaring nature, don't dare to cross the Aryth Ocean.
The Seanchan are of the opinion that they, being the descendants of Artur Hawkwing, have a right to rule the Westlands. They make the people of the conquered nations swear the Oath of Return, which basically means serving them, and try to conform the lands to their ruling system.
- Main article: Corenne
Luthair's descendants planned to return to the Westlands almost as soon as they heard of the fall of Hawkwing's empire, to "take back what was once theirs." Recently, the Seanchan have arrived on the main continent and begun to "retake" the lands. They were intially forced back at Falme by the Dragon Reborn and the Heores of the Horn, but later returned to the south, to conquer Tarabon, Altara and Amadicia, though their incursion into Illian was halted.