Alys Karstark

Alys Karstark is a character that will debut in the seventh season. She will be played by Megan Parkinson. Alys is a member of House Karstark.

In the books
In the A Song of Ice and Fire novels, Alys Karstark is the only daughter of Lord Rickard Karstark, Lord of Karhold, and a headstrong girl who knew Robb Stark and Jon Snow during childhood. She was betrothed to Daryn Hornwood, heir of House Hornwood, until he was killed in the Battle of the Whispering Wood. After Ser Jaime Lannister was released by Catelyn Stark, Lord Rickard promised Alys's hand to whoever brought the Kingslayer to him, in order to avenge the deaths of his sons Eddard and Torrhen, who were also killed by Jaime.

Alys's surviving brother Harrion is taken captive at the Battle of Duskendale. He was imprisoned in Maidenpool, but it has been almost a year since his surviving kin received news about it, and it is uncertain if he is still alive.

Following Rickard's death, his treacherous uncle Arnolf, who secretly collaborates with the Boltons, schemes to take over Karhold: he announces in public that he supports Stannis (intending to stab him in the back while fighting the Boltons), hoping that the Lannisters will execute Harrion as a punishment, then Alys will become the heiress of Karhold. Arnolf plans to force Alys to marry his son Cregan (though he is her first cousin once removed, this is not considered Incest in Westeros). After she gives birth to a son by Cregan, they plan to dispose of her. .

Alys finds out about Arnolf's twofold treachery, escapes to Castle Black and informs Jon what her great-uncle is up to. She has no idea what became of her brother Harrion as a result of Arnolf's fake announcement.

Alys resents Robb Stark for killing her father, stating "I thought the whole reason they marched south was to kill some Lannisters". She knows for what crime her father was executed, but it does not make a difference for her. But, since Jon belongs to the Night's Watch, there is no blood feud between them, and she asks his help to save both her and Stannis from her great-uncle. Jon quickly sends Tycho Nestoris to find Stannis and warns him of the traitor in his host, and he does. Arnolf, his son Arthur and grandsons are arrested and Stannis intends to execute them.

Meanwhile, to keep the Boltons and Arnolf from forcing Alys into a marriage to seize her birthright, Jon quickly orchestrates the voluntary marriage of Alys to one of the wildling chieftains who have become his new allies (specifically, Styr's son).

The TV series significantly condensed the Stannis/Bolton/North plotline, and the Karstark subplot is slightly condensed as well. The TV version essentially condensed Lord Rickard's son Harrion (his last surviving son but opposed to the Lannisters and Boltons) with Rickard's scheming uncle Arnolf (who supported the Boltons), creating the composite character "Harald Karstark", Rickard's last surviving son who sides with the Boltons. Unlike Arnolf, who at least partially sided with the Boltons as a scheme to take over House Karstark, Harold does it purely as revenge for his father's execution by Robb Stark.

Due to the various condensations in the Karstark family tree in the TV series, it is as-yet unconfirmed if TV-Alys will still be Rickard's daughter, or perhaps changed to a grand-daughter or niece.

The general idea seems to remain in the TV version that the Karstark military sides with the Boltons but not all of the Karstark family supported this decision, leaving Alys Karstark as the new heiress who needs to make peace with the Starks.

The TV series also seems to have borrowed the element of Alys Karstark riding north to Castle Black seeking Jon's aid by transferring it to Sansa. In the books, when Jon hears of a Northern girl fleeing to the Wall he at first suspects it might be his sister who was forced to marry Ramsay Bolton (Arya, though it was actually Jeyne Poole posing as Arya in the marriage). He is then surprised to see that it is actually Alys Karstark; in the TV version, it actually is his real sister (the other one, Sansa) who arrives at Castle Black.