As part of his contribution to The World of Ice and Fire, George R. R. Martin created an extensive history of House Targaryen from Aegon I through to the early reign of Aegon III. This material was so substantial that only heavily paraphrased or redacted forms were used in the actual book. These may see later publication in Fire and Blood/The GRRMarillion. However, Martin gave readers a partial taste by taking some of that material and, with the help of Gardner Dozois, editing it down to suit two anthologies which he published.
The first, “The Princess and the Queen”, was published in Dangerous Women and presents an edited down version of Martin’s account of the Dance of the Dragons, refocused on the titular characters and ending before the end of the conflict. The second, “The Rogue Prince”, was published in Rogues and is drawn from Martin’s account of the reign of Viserys I and his relationship with his brother, Prince Daemon Targaryen. These narratives provide more details than The World of Ice and Fire does, but do not provide the same level of completion as the world book does.