The Winterborn are a clan of Reachman who have inhabited the Wrothgar region of the Western Reach, dating back to the First Era. Though they devoutly worship Malacath, they have often been at odds with the Orsimer, and fought against them during the Siege of Orsinium.
Sometime during the Classical Period, they were led by Evandene. During a raid on an Orc village, she showed restraint in 'merely' decimating the populace. Her daughter Mercedene grew livid when she arrived with reinforcements, and challenged her mother on the spot. According to the tale, she said, "Harvesting a tenth of the weeds yields a harder strain of weed. Best to burn the field so its soil can take another crop." She then killed her mother, cut out her heart, and ate it. When Mercedene left the village, the Winterborn rode at her back as she usurped her mother's position and was then on called the "Beast of the Reach". All the villagers were so full of arrows that they "resembled pine cones", and Evandene's corpse decorated the altar to Malacath. Later on, King Joile of Daggerfall hired mercenary bands from the Reach to join him in the Great Siege of Orsinium, the Winterborn noted as being the most accomplished. Joile set up a duel between Gaiden Shinji of the Order of Diagna and Baloth Bloodtusk of the Savage Sons. Unbeknownst to the parties involved, including Joile's own allies, Joile tasked General Mercedene with orchestrating their assassinations, using his archers to kill them both. The Knights of the Dragon, learning of his betrayal too late to stop it, executed Mercedene after she tried to have all the witnesses killed. Her accursed spirit would later haunt Old Orsinium by the Second Era.
Years later in the Interregnum, the Winterborn Clan ruled over Wrothgar amidst the reign of the Longhouse Emperors of the Reach. When the Daggerfall Covenant had formed and the Orcs were diplomatically granted full control of the Wrothgar territory, the Winterborn fought against them as the ongoing Alliance War was raging on in 2E 582. By 2E 582, they'd been forced to retreat into Frostbreak Fortress. King Kurog led a siege to draw them out, having the assistance of the Vestige in killing Urfon Ice-Heart.