The Princess and the Queen
The Princess and the Queen, or, the Blacks and the Greens is an epic fantasy novella by American novelist George R. R. Martin, published in the 2013 Tor Books anthology Dangerous Women. The novella is presented in the form of writings by the fictional historian Archmaester Gyldayn, who is also the "author" of Martin's 2014 novella The Rogue Prince, a direct prequel to The Princess and the Queen.
Source: Wikipedia — The Princess and the Queen (CC BY-SA 4.0)