Under Stewart I's reign, magical restrictions befell all Schools of Magery in the Empire. Many schools were abandoned, and among them was the Skylark School of Magery. The close came suddenly in 762 IE, and very little preperation was made. Judging by corpses in the ruins, the Imperial Army also killed key administrators against closing the school. In the haste, much of the magical waste, toxic sludge, was left in the underground cavern that made up the lowest level of the school.
For a time, the School was forgotten as just another sealed off ruin, and without it Skylark Vale itself became less important. Then, after nearly a century, the poisonous wastes leaked from the underground into the river at the head of the Vale. The river flowed from north, went into the cavern, and then out of the caves, carving its way through most of Skylark Vale.
In the year 836 IE, the poison in the water became noticable. First, there was a bitter taste in the waters. Then, as time went on, the poison in the water started taking more serious effects. The poisons infected and killed many of the inhabitants of the Vale, most notably the children. Meanwhile, the agricultural efforts soon failed due to the Curse, and most crops either became very sickly, or died outright.
Places like Sweetgrove became empty, with people staying indoors and waiting for help. Fort Talrus in the south was not affected due to its distance from the river, and soon a makeshift farm was built outside of the fort walls to help support the rest of the Vale. Similarily, Blinlock had very little effect. As a mining town, it was farther north from the river and didn't suffer as badly from the poisons. Definitely the worst off of all of the cities, Marralis was outright abandoned. Being a farming settlement, when the poisons came the entire economy of the city was obliterated. Most of the farmers there died from the poison, and the rest moved to Sweetgrove as poormen.
Seeing the weakened state of the Vale, many monsters of varying races appeared from various places. Near Fort Talrus, a Kobold infestation was established, and in the northwestern corner of the Vale, Goblins established a settlement. South of Marralis, bandits established a lair to prey on the weak Skylark Vale. All of these parasitic settlements were eventually wiped out by adventurers much later.
The First Evacuation
At this point, those residents with enough money fled, and the economy of Skylark Vale fell dramatically. Some of those able to flee didn't, for various reasons. For example, the mayor of Sweetgrove could not leave due to her duties to both the Vale and the Empire. Seeing the minor success at agriculture in Fort Talrus, some tried establishing farms farther from the river, and most failed. With the rich gone for the most part, the remainder of the citizens were left to wallow in disease and poverty. It remained this way until the eventual cure in 842 IE.
Mayor Crouch of Sweetgrove posted many pleas for help in various boards, as well as requesting aid from the Empire. The Empire denied, seeing no problem in such a peacful area. Many adventurers tried their hand at curing the Vale, and most failed. However, in the year 842 IE, a particular band of adventurers arrived in Fort Talrus. After investigating and speaking with many of the surviving inhabitants of the Vale, the group eventuall opened the ruins of the Skylark School of Magery. Determinedly, they descended into the depths, fighting off infestations of monsters ranging from Goblins to Gremlins, and reportedly they found a colony of Giant, Intelligent, Friendly Spiders, and the Dragon Pythras.
Eventually, the group made their way into the lower half of the school, which was infested with mutated Alien Beasts. Reportedly, it was here that the adventurers met a small party of Vahnatai, not of the Olgai Tribe, trying to cure the poisons. The adventurers found the reason for the Curse, the poisons leaking into the river. Pushing onwards, the adventurers found a scepter instrumental to curing the diseased of the Vale. Eventually, after fighting their way down, they arrived at the area designated for cleansing the poisons before the closing of the school, as well as finding the corpses of several adminstrators. Activating the controls, the loosed Quickfire onto the poisons.
Soon, the source of the poisons was cleansed by the Quickfire, and the adventurers were reportedly rescued by the Vahnatai, teleported to Sweetgrove. Here, they recieved payment from Mayor Crouch, and promptly left the Vale, their task complete.
The Second Evacuation and Cleansing
Either by word of mouth, or by a report from Mayor Crouch, the Empire became aware of the poisons. The Empire sent rescue workers to Skylark Vale, and its inhabitants were evacuated to safer fields. These wokers, apart from evacuating the Vale, also immediantly began proper measures to cleanse the river. Though the main source of the poison was destroyed by the adventurers when they released the Quickfire on the poison, the river was still poisoned, and there was still much waste. Sanitary agents worked for many years to destroy the poisons, but some many years later, the soil and river was once again clean, and resettlement of Skylark Vale began.