Isal Dao, one of the candidates for Phraya of the Southern District of the Stone Throne, was not a patient man. Nor was he one who was likely to succeed on his own merits. Unpopular with the commoners, seen as slimy and unreliable by the lai, and thought of as a pervy joke by the other isal, he basically had no chance. Until he was recruited by the Red Lantern Society. By joining with that devil cult (pledged to Gethry'al'Abyoza, lieutenant of Family Abyoza), he gained access to the devil's influence and (more importantly) money. He started a line of brothels, recruiting only the most beautiful men and women. He augmented their numbers (and their seductive grace) with succubi pledged to Abyoza, although he had them tame their life-draining powers. Instead, they worked their charm, gathering blackmail on the movers and shakers of the district. For a while, things were looking good for a straight-forward political campaign. His new master, however, had other plans. He planned to breed himself a foothold, much like other families had done in the Jinse Empire far to the east. He began (with willing subjects at first) impregnating women by his fiendish subordinates, as well as using women possessed by succubi to gather seed from target males. When there weren't enough willing victims, he turned to kidnapping the "unwanted" (in the name of "clearing the streets of the undesirable") and shipping them to camps to be used as breeding pools.
But then the Ship People arrived, and Dao (and Gethry) saw an opportunity to accelerate the process. Dao, through his Red Lantern allies, reached out and struck a deal. The sena'ka would raid to the east, into his rival Isal Dara's territory, while he accelerated his plans and lent covert support. Things were going well. Then the pesky adventurers of the Dimwit Syndicate arrived. They stopped a major push by the sena'ka and devil allies, and alerted the army to his involvement. Once his hand had been tipped, he began mustering for outright rebellion.
At first, he mainly used his outlaw and mercenary hirelings to stage false-flag attacks on bordering villages to get the people to flee to his territory for safety. Those that arrived were processed into the breedable, and the expendable. The expendable were brainwashed, given weapons, and sent to the front lines as canon fodder. The breedable were sent to the camps. As things escalated and the Stone Throne army arrived in late 211 AC, the situation reached a stalemate. Dao didn't have enough strength to actually make progress, but the army was distracted by dealing with the Ship People, who had landed in force. While several battles took place near the southernmost tip of Lake Thom, and other naval battles took place on the lake itself, the battle lines didn't move for nearly two years. Infiltration was blocked by Gethry's servants, who had maintained a watching eye over the entire rebel nation. It wasn't until a strike force of Handmaidens and adventurers, aided by the devil Iago'vel'abyoza (who had become involved with the Dimwit Syndicate earlier) slipped through the lines and assassinated the key cambions commanding the Red Lantern. With them gone, the infernals were banished to their Astral realm, and Dao's forces collapsed. Dao, who had become almost entirely a figurehead by this point, a mouthpiece for Gethry, tried to flee but was caught by his "concubines" (really slaves he kept for sexual purposes) and was beaten to death. Thus ended the Devil's Rebellion.
One main side effect of this is that the area (now belonging to the Serpent Dominion) is known for the abnormally-high numbers of devil-touched births (nearly 1 in 6 births show markings, and the trend is stable two generations later).