Lord Richard York was present at the Sack of King's Landing, fighting on the side of House Lannister.

Ser Robert York personally slew Ser Robb Reyne who fought for Daemon Blackfyre. The Yorks fought on the side of King Daeron II Targaryen during the Blackfyre Rebellion. House York sided with their liege lords during the Dance of the Dragons as part of the Greens. In gratitude, Loren, afterwards Warden of the West, would go on to ransom Wolfsbane from King Aegon Targaryen and return it to the young son of Edward. Lord Edward York would fight at the side of King Loren Lannister at the Field of Fire, dying while pushing the king away from the flames and saving his life. Legend tells it that the sword was taken from a Manderly Knight but this is uncertain. The sword gained that name after being used by Lord Henrik York to slay a Stark king during a war, hundreds of years before the Conquest. The house would come into possession of a Valyrian steel bastard sword named Wolfsbane. The king would then grant him the lands, titles and incomes of House Crossly, which went extinct with Lord Seamus' death, and thus House York of Red Cliff was founded. Orwen, who would take on the family name York in honor of his father, would go on to fight by his king's side in the War of Ironman's Bay, where he personally slew the rebel Lord Seamus Crossly, the lord of Red Cliff, as well as saved king Tommen's life. Similarly, his son Orwen would receive great favor and be dubbed a knight by the king himself. Yorkoth would go on to marry a daughter of House Banefort, probably as a reward for his services. In this role, he managed to triple the incomes of House Lannister and gained great favor for his house.

At the court of the child King Tommen III Lannister, he impressed the king and was eventually made his Lord Treasurer. He fled to Westeros and eventually found his way to the Kingdom of the Rock. Yorkoth was a talented trader and blacksmith from Qohor before he was forced into exile by his enemies. House York traces its descent to Yorkoth of Qohor, who lived 1,200 years before Aegon's Conquest.

They have the richest emerald mines in Westeros. The lands of House York are fertile and their mines possess an abundance of precious stones, emeralds in particular. At the foot of the mountain is located a large town, dubbed Yorktown after the house. The castle is located on a sizeable plateau. House York's seat is located in the northeastern Westerlands at the castle of Red Cliff, so named due to its reputation as an impregnable fortress, whose forces have successfully destroyed over a dozen armies. Her heir is Edward York, her son by her husband Ser Myles Crakehall. Its ruler is Lady Elizabeth York, the eldest daughter of Lord Richard York and his wife, Lady Elenda Lannister. The house possesses the large trading town, Yorktown as well as the largest emerald mines in Westeros. His son Orwen York married a Lannister princess and received the lands, titles and incomes of Red Cliff in the aftermath of the War of Ironman's Bay and became Lord of Red Cliff. It was founded by the Qohorik exile, blacksmith and trader - Yorkoth of Qohor, who came to the Kingdom of Rock and became King Tommen III Lannister's Treasurer. The House rules over the lands, mines and holdings of the castle Red Cliff, which is situated on a large plateau in the mountain range of the northeastern Westerlands. House York of Red Cliff is a noble house from the Westerlands and one of the principal bannermen of House Lannister of Casterly Rock. No to mention their emerald mines and booming trade.' ―Tyrion Lannister on the Yorks. They are doing rather well I should think. Not to mention Lady Elizabeth is a favorite of his. ' House York are my father's strongest vassals.

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