The Keohso clan is one of the noble houses of the Fire Nation. Descended from the warlords before the nation's unification, the clan retained the right to govern its home island of Shuhon, and the retention of household troops. The clan's family crest is a winged peony.
Lady Sulan of the Keohso clan became the wife of Fire Lord Chaeryu. She died in childbirth having a son, Zoryu. Chaeryu's decision to marry Sulan inflamed the rivalry between the Keohso and their traditional rivals, the Saowon clan, as Lady Huazo of the Saowon had been Chaeryu's mistress and lover before his marriage to Sulan.
Zoryu came to the throne on his father's death. Although the Fire Lord was somewhat unpopular due to the poor harvests and fisheries during the first years of his name, the Keohso remained fiercely loyal to the crown, due to Zoryu's mother having been Keohso. Tensions at the royal court escalated as Zoryu's illegitimate half-brother, Chaejin, gained influence and support for his own claim, and hoped to provoke the Keohso into an act of violence against the Saowon that would be just cause for war. Zoryu noted that he could not even consider abdicating, as the Keohso would immediately take their vengeance upon the Saowon.
As the Saowon gained power and influence across the other Fire Islands, Shuhon Island remained the last location where Lady Huazo did not own properties. However, in 295 BG, she purchased a salt-making operation and vacation house in North Chung-Ling on Shuhon Island, hoping to provoke the Saowon with her vanguard.
Sanshur Keohso, patron of the Festival of Szeto celebrations in North Chung-Ling, grew angered at the purchase. The Keohso were grievously offended when a member of Huazo's vanguard spat on the ground, and threw rocks at Huazo, although a fight was averted by Avatar Kyoshi. Kyoshi warned the Keohso from instigating fights, but Sanshur claimed that as loyalists of the crown, they should not be punished. When a young Keohso vendor put up a Saowon banner to do business with the other clans, his own uncle and other relatives beat him bloody. Kyoshi took the town jail, but the Keohso judge appeared to be very lenient on the offenders.
The following morning, the Keohso were greatly offended after a message appeared in North Chung-Ling's melonyam fields, supporting Chaejin as Fire Lord. Though the Saowon claimed it was a spiritual message, Sanshur claimed it was Saowon treachery, but had to emphasize his beliefs, as the other residents of North Chung-Ling were uncertain what to believe. A true fight broke out between the Saowon and Keohso forces after Rangi punched Koulin across the face.
Although open war managed to be averted, Zoryu intended to render all the clans irrelevant, including the Keohso, recognizing that there could be no true strength in the Fire Nation until its citizens were loyal only to the Fire Lord instead of the clans.