A King is the ruler of a monarchy or realm. Kings usually inherit their position by birth and rule for life or until abdication. A female who rules as King is a Queen.
The offspring and siblings of Kings hold the title of Prince or Princess.
- The King of the Andals and the First Men, who rules the realm known as the Seven Kingdoms of Westeros. The title was created by Aegon the Conqueror, who unified the seven independent kingdoms of Westeros under a single monarchy known as the Iron Throne.
- The King in the North, the head of House Stark, who ruled the Westerosi region of the North, since the Age of Heroes to the War of Conquest, and briefly during the War of the Five Kings. Title established by Bran the Builder and held by his descendants for thousands of years.
- The King of the Iron Islands, who ruled over the Iron Islands, as well as several other locations of western Westeros, particularly the Riverlands. The title was held by several dynasties, including House Hoare and, more recently, House Greyjoy - the latter reviving the ancient title during the Greyjoy Rebellion and the War of the Five Kings.
- The King-Beyond-the-Wall, an elected monarch of the Free Folk.
- The King of the Rock, who, following the Andal invasion, extended their rule over the Westerlands. The title was originally held by the head of House Casterly and then by House Lannister.
- The King of the Reach, the head of House Gardener, title established during the Age of Heroes by Garth Greenhand. Following the Andal invasion, the King of the Reach ruled over the entirety of the eponymous region.
- The King of the Rivers and the Hills, who ruled over the lands surrounding the Trident until the Andal invasion.
- The Mountain King, a dynasty of the First Men ruling over the region that would become known as the Vale of Arryn, until the Andal invasion.
- The King of the Mountain and the Vale, a line established by Ser Artys Arryn, who usurped the Eyrie and the lands subject to its rule, after defeating the Griffin King, the last Mountain King.
- The Storm King, title first held by Durran Godsgrief, and later by his descendants, House Durrendon. The Storm Kings extended their rule over the Stormlands.
- The King of Qarth, who ruled over the city of Qarth until the Qartheen rebelled against their rule.