Euron Greyjoy

"I still remember seeing my father's fleet burn in Lannisport. I believe your uncles were responsible."

- Tyrion Lannister

Euron Greyjoy is a character in the sixth season, though he was previously mentioned indirectly in the Season 1 episode "Cripples, Bastards and Broken Things". He will be portrayed by Pilou Asbæk. He is the younger brother of King Balon Greyjoy, and the eldest uncle of Theon and Yara Greyjoy.

Background
Euron Greyjoy is the younger brother of Balon Greyjoy, head of House Greyjoy, Lord Reaper of Pyke and self-fashioned King of the Iron Islands.

Season 1
Tyrion Lannister tells Theon about his memories of witnessing the Raid on Lannisport which Tyrion says was caused by Theon's uncles.

Season 6
In the wake of the deaths of Tywin Lannister and Stannis Baratheon, Euron returns to the Iron Islands.

In the books
In the A Song of Ice and Fire novels, Euron is a wildly unpredictable man, known for his delight in playing vicious mind games and waging psychological warfare on anyone and everyone around him. He is hated by all his brothers, particularly Victarion. He wears a patch over his left eye, which is nicknamed his "Crow's Eye", though it is unclear what he hides beneath the patch.

Euron has never been married. He has several bastard children, but does not have any regard for any of them, none were officially acknowledged, and none have been introduced in the narrative.

Several years ago, Euron seduced - perhaps raped - and impregnated Victarion's third wife, which drove Victarion to beat her to death so he would not be put to shame as a cuckold. Only the taboo against kinslaying kept Victarion from killing Euron too. As punishment, Balon exiled Euron from the Iron Islands, so he is not present when Theon returns to Pyke. Victarion deeply hates Euron for that and wishes him dead.

Euron's actions also made him very unpopular with the Drowned Men priests, who deride him as an "ungodly" man. There aren't many things that the Drowned God religion won't stand for - given that it considers raiding and pillaging to be holy acts - but raping (or seducing) your own brother's wife is one of them.