Ironborn

The ironborn or (rarely) ironmen are the natives of the Iron Islands off the west coast of Westeros. They are a fiercely independent sea-faring people who chafe at the rule of the Iron Throne. Their deity is the Drowned God.

The Iron Islands are ruled by House Greyjoy from the castle and island of Pyke. Lord Balon Greyjoy rules the Islands. His only surviving son and heir is Theon Greyjoy who was formerly a ward and hostage of Lord Eddard Stark at Winterfell.

In the books
The ironborn are an intermingling of the blood of the original First Men settlers of the islands and the Andals who followed six thousand years later. Whilst the Andals and the Faith of the Seven came to dominate everywhere else below the Neck, they found less purchase on the Islands. Whilst some converts and adherents of the Faith were found, most of the invaders were actually convinced to worship the native deity, the Drowned God, instead.

The ironborn consider reaving and piracy to be their birthright, and fear that three centuries of peace under the Iron Throne is destroying their heritage and removing their edge, especially as the Seven have found more purchase on the Islands since the Targaryen invasion. Nine years ago, to reverse this trend, Lord Balon declared independence in the Greyjoy Rebellion but was soundly defeated. Since then the ironborn have remained quiet vassals of the Iron Throne.