As recorded in Curse Of Strahd, Fiona Wachter came into power as the new Burgomaster of Vallaki following the Riots Of The Blazing Sun. Compelled by visipns of sunlight upon the town, she immediately initiated sweeping changes to its structure. As many suffered Dream Pastry withdrawals due to a lack of shipments of Dream Pastry from Old Bonegrinder, Fiona lifted many of the draconian punishments that Vargas Vallakovich had imposed on his citizens.
She had the statue of Vyacheslav Vallakovich torn down from the Vallaki Town Square's fountain, and reinstated it with a stone sculpture of Strahd von Zarovich. She also opened the gates to the Vistani and began fostering a relationship with the nearby Vistani Camp. Over time, she began to bear the Mark of Strahd herself, and assembled a large militia of black-cloaked guards loyal to a cult devoted to her. Fiona also deemed Ravens a symbol of bad luck and to be killed on sight, as were foreign adventurers.
Fiona's vision that the blood of adventurers were needed to save Vallaki led to small parties of hunters seeking to kill adventurers across Barovia in exchange for coin; however, this loyalty to the Wachters wavered somewhat after the Lighting Of The Silver Beacon. This event had been initiated by a group of foreign adventurers composed of Ghalwin of the Grove, Ajuni Elajoral, Tobias Villie Broadnose Cogsmith, Ezmerelda D'Avenir, and Mormeros Fayan. After Mormeros was killed in a battle against Strahd, this group would travel to Vallaki, alongside former guard captain Izek Strazni, and initiate a quiet revolution.
Using Spells to make them invisible, they infiltrated the Wachterhaus and kidnapped both Fiona and Stella Wachter, while locking Karl Wachter and Nikolai Wachter II in a room alongside the family's personal guards. With evidence they gained from the raid, they called for an emergency town meeting at the burned square, and put Fiona on a trial. Public sentiment was initially firmly against the adventurers, who had only exacerbated the anti-foreigner propaganda by kidnapping the ruling family and forcing a trial; however, through the creation of magical food and acts of might, they quieted the crowd and started their case. Izek forcibly took Nikolai II and Karl into the crowd, physically ensuring they would not act out.
Despite protests by Fiona, Ajuni and Ghalwin presented damning evidence of her relationship with Strahd. They submitted land deeds given to the Wachters by Strahd's alias "Vasili von Holtz", two evil tomes related to Fiendish summoning, as well as the dead body of her slain Imp Majesto. Using this relationship, they called her character into question, which was exacerbated when they revealed that she had been sleeping with the body of her dead husband Nikolai Wachter, kept fresh with necromancy. Finally, they challenged her argument that only she could bring dawn to the people, as Ajuni lifted the Holy Symbol of Ravenkind and showed Vallaki the first sunlight it had seen in centuries.
Moved by the speech and sunlight, the crowd turned. As a mob began to bay for blood, Tobias stopped turned fate with a speech of mercy; an endless cycle of revolution would only continue to hurt Vallaki. A pardon was agreed for the Wachters, provided that they be banished from the town. With her ousted as Burgomaster, Vallaki experienced its first true moment of unity; as townsfolk hugged and cheered, the revolutionaries were thereafter dubbed the Heralds of Dawn.
In the aftermath of the trial, a mercantile republic was established, with community leaders from Saint Andral's Church, the Arasek Stockyard, the Blue Water Inn, Blinsky Toys, and other businesses representing a semi-formal town council. The Wachterhaus was designated to become the "Fayan Academy", named after the hero who perished, and a system of education was set to be implemented. The Wachters themselves were taken to the Herald's base at Argynvostholt, along with a militia of 10 guards and hunters, and the fort was established as a second base outside town walls.