Princess Rhaena Targaryen, one of the Black Brides of King Maegor I, was the eldest of the six children of King Aenys I Targaryen and Queen Alyssa Velaryon. She was a dragonrider and rode the dragon Dreamfyre.
Soon after her birth Queen Visenya Targaryen proposed marrying Rhaena to her uncle, Prince Maegor, but the High Septon mounted a vigorous protest. Maegor was married to the niece of the High Septon instead, Lady Ceryse Hightower.
In 41 AC King Aenys I Targaryen arranged the marriage of Rhaena to her brother, Prince Aegon, which caused an uprising of the Faith.The marriage to her brother lasted for only three years, during which she gave birth to twin daughters: Princess Aerea and Princess Rhalla.
When Rhaena's father King Aenys I died, Rhaena and her husband were being besieged at Crakehall by members of the Faith. Instead of Aegon becoming king, Dowager Queen Visenya brought Prince Maegor back from Essos, and made sure he was crowned king.
Prince Aegon and Princess Rhaena sought refuge from King Maegor the Cruel. At one point, Lord Lyman Lannister protected the prince and princess under his roof, extending guest right and refusing all the king’s demands to turn them over. Yet Lord Lyman did not pledge his swords to Aegon and Rhaena.
When Prince Aegon died in 43 AC, Rhaena became a widow. Rhaena took refuge on Fair Isle, under the protection of Lord Farman, who hid her and her daughters. It was Tyanna, one of Maegor's queens, who found them. In 47 AC, Rhaena was forced to wed Maegor. As she was one of the three women who was wed to Maegor under force, who had been proven to be fertile, Rhaena would become known as one of the "Black Brides".
When Rhaena learned that her youngest brother, Prince Jaehaerys, was claiming the throne for himself, she fled King's Landing on her dragon Dreamfyre, stealing Blackfyre away as her king and husband slept to join Jaehaerys' cause.