Rognar II Greyiron

King Rognar II Greyiron is an unseen character in Game of Thrones. He was the King of the Iron Islands during the Andal Invasion of Westeros.

Biography
When the Andals attacked the Iron Islands in an attempt to convert the Ironborn to the Faith of the Seven, they were able to bring down and kill King Rognar, but they eventually turned to the Drowned God themselves.

Reference

 * "The Drowned God (Histories & Lore)"