Gyldayn was an archmaester of the Citadel renowned for his works about the history of House Targaryen.
History[]
Gyldayn was the author of Fire & Blood, Being a History of the Targaryen Kings of Westeros which includes The Sons of the Dragon, on the reigns of King Aenys I Targaryen and his brother, Maegor I Targaryen; The Rogue Prince, about Prince Daemon Targaryen, and The Princess and the Queen, a history of the Dance of the Dragons.
Gyldyn shared his uncompleted work with Archmaester Perestan, and later allowed Maester Yandel to use some of his passages in his work, The World of Ice and Fire. Gyldayn is said to have lived into the rule of King Robert I Baratheon.
Behind the Scenes[]
In the real-world book, The World of Ice and Fire, the character of Gyldayn is used to represent passages written by George R.R. Martin, whilst Yandel represents writings from his associates, Elio Garcia and Linda Antonsson.