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King of the Three Sisters
King of the Three Sisters or Queen of the Three Sisters, if female, was the title held by the monarch of the Three Sisters, an archipelago located in the Bite. The monarch was a member of House Sunderland.
Prior to the arrival of the Andals and the Faith of the Seven, the Sistermen were an independent people with their own religion, worshipping deities known as the Lady of the Waves and the Lord of the Skies. Their monarchs also acted as pirate kings.
According to maesters, two thousand years ago the islands were conquered by the North in an invasion known as the Rape of the Three Sisters. In response, the Sistermen bent the knee to the Eyrie to expel the northmen, ending the era of kings on the Sisters and putting the archipelago under the rule of the King of Mountain and Vale. Conflict over the islands would continue for a thousand years in the War Across the Water.
During the Targaryen conquest of Westeros, the Sistermen rebelled against House Arryn, declaring Marla Sunderland as their Queen. She was deposed, however, when a Braavosi fleet hired by House Stark at the behest of Aegon the Conqueror approached the islands. Marla's brother bent the knee while she ended her days as a silent sister.