Master of War

Master of War was a position in the government of the Seven Kingdoms. It served as the supreme commander of the armies of Westeros.

The post appears to be a new position invented by Cersei Lannister. She intended for her uncle, Ser Kevan Lannister, to serve as Master of War under King Tommen Baratheon. However, he declined and instead returned to Casterly Rock, rather than serve as a puppet of his niece.