Warden

"I, Eddard of the House Stark, Lord of Winterfell and Warden of the North, sentence you to die."

- Eddard Stark to Will

Warden is a title bestowed upon the head of a Great House by the ruler of the Seven Kingdoms. The Wardens command the armies of one of the constituent regions of the Seven Kingdoms in the name of Iron Throne for the defense of the entire realm. Thus any one Warden is expected to lawfully command a quarter of all armies in the realm during a time of crisis.

By custom, the title is functionally hereditary. However, a Warden does not necessarily have to also be one of the Lords Paramount (rulers of the constituent regions of the realm) though this is almost always the case. For example, if an elderly or infirm ruler came to be the head of House Lannister, the office of Warden might be delegated to another family member young and capable enough to lead armies in the field.

Littlefinger implies that a woman appointed to the title would be properly known as a "Wardeness".

Currently, there are no Wardens; the Wardens of the North, West and South have died and have yet to be officially replaced, while the Warden of the East has declared for the Kingdom of the North.

Current Wardens of the Seven Kingdoms

 * Warden of the North:  Title traditionally held by the Lord Paramount of the North and Lord of Winterfell, the head of House Stark, since Torrhen Stark, the last King in the North. Held by the head of House Bolton after they usurped House Stark during the Red Wedding and returned to the North under the authority of the Iron Throne. With the extinction of House Bolton in the Battle of the Bastards and the subsequent declaration of the North as an independent kingdom, the title is currently vacant.


 * Warden of the West: Title traditionally held by the Lord Paramount of the Westerlands and Lord of Casterly Rock, the head of House Lannister, since Loren I Lannister, the last King of the Rock. Previously held by Lord Tywin Lannister, the title is currently vacant. It was possible that the position was held by Tywin Lannister's brother Kevan Lannister up until the latters death, since Jaime was a member of the Kingsguard and his son Lancel was a member of the Faith Militant. It is likely that he would have inherited this position in addition to being the Lord Paramount of the Westerlands and the Lord of Casterly Rock. It is also possible that Queen Daenerys Targaryen might recognize her lord hand, Tyrion Lannister, as Warden of the West and that she might appoint him to that position should she take the Iron Throne.


 * Warden of the East: Title traditionally held by the Lord Paramount and Defender of the Vale and Lord of the Eyrie, historically the head of House Arryn, since Ronnel Arryn, the last King of Mountain and Vale. Lawfully held by Robin Arryn, the child Lord of the Eyrie, but with their declaration for House Stark, the title is officially vacant.


 * Warden of the South: Title traditionally held by the Lord Paramount of the Reach and Lord of Highgarden, the head of House Tyrell, since Harlen Tyrell, steward to the last King of the Reach, who surrendered Highgarden and the Reach to Aegon the Conqueror. After the attack on the Great Sept of Baelor and the Fall of Highgarden and thus of House Tyrell itself, the title is given to Lord Randyll Tarly, as the reward for his betrayal of House Tyrell.

In the books
Typically, the Warden of the North defends against wildling attacks that come south of the Wall. The Warden of the West, from House Lannister, defends against coastal raids from the Iron Islands. House Greyjoy weren't chosen to be Wardens, because more often than not, they are what the Warden of the West is defending against. Even though they submitted to the Iron Throne, illicit ironborn raiding would occur from time to time and would have to be suppressed. The Warden of the South, from House Tyrell, would defend against border skirmishes with Dorne, as Dorne actually retained its independence for two centuries after the Targaryen Conquest, and was only united to the realm (by marriage alliance) a century before the War of the Five Kings. This is why House Martell of Dorne is not the Warden of the South. The Warden of the East, from House Arryn, seems to have defended against raids or invasion from the Free Cities across the Narrow Sea, such as the threat during the War of the Ninepenny Kings when an invasion was mounted from the Stepstones in the Narrow Sea.

House Tully were not Wardens, probably because the Riverlands are centrally located within the realm and far from external threats. It is not clear why House Baratheon were not named as Wardens, as the Stormlands border Dorne to the south (and thus they could have been Wardens of the South), and also border the Narrow Sea like the Vale (and thus could have been Wardens of the East). The Tyrells may have been chosen as Wardens of the South due to the larger army and population of the Reach, and because more Dornish attacks may have been targeted at the fertile lands of the Reach instead of the forests of the Stormlands. House Arryn may have been chosen ahead of the Baratheons as Wardens of the East because they had to deal with contentious Hill tribes in their mountains and thus needed the military assets at their disposal to deal with them. Also, the Andal Invasion thousands of years ago began in the Vale of Arryn, so it has been used an invasion corridor across the Narrow Sea before.

After Jon Arryn died, Queen Cersei managed to convince King Robert to name her brother Jaime Lannister as the Warden of the East, because Jon's only son and heir Robert "Sweetrobin" Arryn is just a child. This greatly angered many lords in the Vale because Jaime has no connection to House Arryn or the Vale, so they begin to defiantly refer to Sweetrobin as the "True Warden of the East". Ned Stark is also opposed to Robert's decree because it puts the armies of two regions under command of a single house. Jaime, however, never actually travels to the Vale or makes any attempt to take command of the Vale's armies during these few months, and thus his hold on the title was entirely nominal. Jaime continues to technically hold the position while he spent a full year as a prisoner of the Starks after the Battle of the Whispering Wood, although his imprisonment meant that the position was left officially vacant. The title of Warden of the East is restored to Sweetrobin by Tywin Lannister as one of the conditions of the marriage-alliance between Lysa and Petyr Baelish which brings House Arryn back into the Lannister fold. The TV series omitted this entire subplot.

Following Tywin's death, Cersei gives the title of Warden of the West to Daven Lannister, son of Ser Stafford Lannister - not because she trusts Daven, but due to an unpleasant discussion with Kevan, who rejects the post of Hand of the King after Cersei refuses to name him Lord Regent as well and relocate to Casterly Rock. Daven does not regard his appointment lightly, but he feels that his uncle Kevan should have been chosen for that office.

By the point the books reached, the four major Wardens of Westeros are as followed:
 * Warden of the North: Roose Bolton
 * Warden of the West: Daven Lannister
 * Warden of the East: Robert Arryn
 * Warden of the South: Mace Tyrell