The Feast of Saint Andral's was a disaster that occurred in the town of Vallaki, long considered a safe haven from the Undead that terrorized the rest of Barovia. Saint Andral's Church had long been a sanctuary in Vallaki, its land consecrated by the bones of the Paladin Saint Lugdana Andral, interred in a crypt beneath the altar. Few knew of this secret, and fewer still understood that the bones were the source of the church's Consecration. When a desperate gravedigger, Milivoj Temesvari, sold her remains to the coffin-maker Henrik van der Voort, that protection quietly lapsed.
In truth, the elements of this all stemmed from a conspiracy to have the bones removed. Weeks before, Henrik had been approached by the nobleman Vasili von Holtz, who offered life-changing coin in exchange for having the bones removed. Henrik repeatedly requested that Milivoj to divulge the church's secrets; he was initially rebuffed, but Vasili returned with a "solution". He brought six Vampire Spawn who stayed upstairs in the Coffin Maker's Shop, traced a Glyph on the door, and the gravedigger grew mysteriously sick and increasingly desperate. In exchange for the coin, Milivoj finally relented, not realizing that the removal of the bones lead to the removal of Consecration on church lands.
A group of traveling Adventurers known as the Pack uncovered the conspiracy and moved to resolve it. They cured the Curse afflicting Milivoj and traced the bones to the shop, and confronted the vampire spawn directly. The fight spilled from the top floor of Henrik's shop down to the Vallaki Town Square, where five spawn tore through civilians and soldiers alike. The vampires proved to only be effectively fought off by the head guard Izek Strazni, the Pack, the traveling Atlas Atruvian, and a mysterious Wereraven, but they routed the lot, including former adventurers Brokk M'odag and Xana Habblegabble Goldworthy.
As it looked like the spawn were being contained, the Count Strahd von Zarovich arrived for the first time in centuries. He appeared from nowhere, flying above the square atop Beucephalus, having been alerted by a Glyph when the Pack engaged with his spawn. What followed was brief and absolute: he immolated a ring of soldiers and the last cowering spawn with a single Spell. When he encountered the Pack, he saw that Ireena Kolyana had clearly fallen in love with the Giantborn Jarmo Maulgrave. Enraged, he put them both under a magical Enchantment, then took both Ireena as well as Jarmo's Dreamweave Circlet.
As Shakti of the Wildhunt targeted him and Ghalwin of the Grove charged with a cadre of soldiers, Strahd easily repelled them both, then immolated the town guard for good measure. He had taken what he had come for, and left atop his Nightmare, leaving only a square of ash and silence. Jarmo's curse petrified him, leaving a monument of Strahd's wrath. The bones were recovered and the church reconsecrated before nightfall, with Jarmo's body being placed below the altar.
By the town's reckoning, the crisis had been contained, the church restored, and the outsiders had proven their worth. However, the town's morale had been completely shaken to its core. The Vallaki Burgomaster's Mansion doubled the guard, expanded the stockades in the square, and Vargas Vallakovich announced a new festival, the "Festival of the Blazing Sun", with greater urgency than any before it. More of the town's scant resources were spent on protecting the Vallakovich family than ever before, and now doubting that their burgomaster's mantras protected them from Strahd, the town began to rebel.
The Feast of Saint Andral's was the most important catalyst to the Riots Of The Blazing Sun, in which the Vallaki town structure would flip wildly.