Alys Karstark daughter of Rickard Karstark

Alys is born in 284 AC at Karhold, the only daughter of Lord Rickard Karstark. As a child she is betrothed to Daryn Hornwood, heir to Hornwood, to wait until she is old enough to marry.

In 290 AC, at only six years old, she travels with her father to Winterfell. Lord Rickard hopes the girl will charm Robb Stark and so improve on the match already sealed with the Hornwoods. Alys dances with Robb, whom she finds courteous, and with Jon Snow, more reserved.

Her brothers Eddard and Torrhen Karstark die in the Battle of the Whispering Wood, along with Daryn Hornwood, Alys's betrothed, at the hands of Ser Jaime Lannister.

After Jaime Lannister's escape, Lord Rickard promises Alys's hand to whoever brings him the Kingslayer's head, the man who has taken two of his sons from him. Vargo Hoat captures and mutilates Ser Jaime hoping to win Alys that way, and with her, lordship over Karhold.

With her father and brothers dead, Karhold falls into the hands of Arnolf Karstark, Alys's great-uncle, who plans to marry her to his own son to seize the castle. Alys flees her cousin and rides for the Wall seeking help.

Weakened, she is found on a dying horse near Mole's Town and brought to Castle Black. There she tells Jon Snow, Lord Commander of the Night's Watch, that Arnolf plans to betray Stannis Baratheon on behalf of Roose Bolton, the new Warden of the North.

Jon instead arranges Alys's marriage to Sigorn, Magnar of Thenn, founding a new house that could claim Karhold should her brother Harrion die. Melisandre performs the ceremony at Castle Black, where Alys and Sigorn leap together over a burning trench.