Protector of the Realm

"Protector of the Realm" is a title in the Seven Kingdoms, the holder of which is considered to be head of state. The title is usually held, ex officio, by the King of the Andals and the First Men who sits on the Iron Throne. During the minority of a child monarch, however, a regent may officially be named as Protector of the Realm until the heir comes of age.

The title was (presumably) created by the Targaryen Kings when they unified the Seven Kingdoms into a single realm during the War of Conquest.

==Season 1

King Robert Baratheon's full title is "King of the Andals and the First Men, Lord of the Seven Kingdoms, and Protector of the Realm".

After King Robert is mortally wounded by a boar while hunting, he dictates his final orders to Hand of the King Eddard Stark, naming Lord Stark as regent and Protector of the Realm until his heir comes of age. Renly Baratheon correctly assumes that the dying Robert has given orders to this effect, as does Petyr Baelish. After Robert dies, Eddard arrives at court to find Joffrey Baratheon seated on the Iron Throne and introduced as both the new king and Protector of the Realm. However, Eddard has Ser Barristan Selmy read King Robert's final order before the royal court, naming Lord Stark as Protector of the Realm. Eddard proclaims that Joffrey has no claim to the throne, and orders the City Watch under Janos Slynt to take Joffrey and Cersei into custody. This sparks a standoff between Stark's personal guards and the Kingsguard, as Joffrey demands that Stark and all of his men be killed. Just then, Baelish and the Goldcloaks betray Eddard, killing all of his men and taking him prisoner. Joffrey then continues to technically hold the title of Protector of the Realm, though his mother Cersei still acts as Queen Regent.