The Riverlands

"The Riverlands is our home and Gods help us we love it. Still...they say "The King eats and the Hand takes the shit". The same is true of the Riverlands. The Seven Kingdoms piss and the Riverlands change clothes."

- Ser Brynden Tully

The Riverlands is one of the constituent regions of the Seven Kingdoms. They have been a frequent battleground in the civil wars that have afflicted the Seven Kingdoms and also in the wars that took place between the old nations of the continent before the Targaryen Conquest. During the time of the First Men, the Riverlands were an independent kingdom known as the Kingdom of the Rivers and the Hills.

Located roughly in the center of the continent, and with few geographical boundaries such as mountains, for centuries it has been a borderland between surrounding strong kingdoms. The Riverlands were ruled by the ironborn at the time of the Targaryen Conquest, and Aegon the Conqueror's assault was assisted by a popular uprising led by House Tully. For this reason the Riverlands didn't have a king at the time of the invasion, and the Riverlands are not technically counted as one of the "Seven" Kingdoms (instead essentially making up the eighth "kingdom"). However, for administrative purposes, the Riverlands and their rulers are equal to any other region of the realm.

The Riverlands are ruled from the castle of Riverrun by House Tully. Bastards born in the Riverlands are given the surname Rivers.

Geography
The Riverlands are dominated by the watershed of the Trident River, so-called because of its three major tributaries - the Green Fork, the Blue Fork, and the Red Fork - which converge at Ruby Ford in the east. The Green Fork is the northernmost, running north-to-south almost up to the Neck near the entrance to the Stark-held North. The Green Fork is only traversable via the castle-bridge complex known as The Twins ruled by House Frey. Thus, large armies attempting to move into or out of the North are faced with only two, predictable choices: travel along the Kingsroad as it crosses the Ruby Ford to the east, or cross the Green Fork at the Twins to the west, which requires paying an often steep toll to House Frey.

The Blue Fork is south of the Green Fork, and terminates near Seagard. The Red Fork is the southernmost and winds its way through the heart of the Riverlands, between the Red Fork and the Gods Eye lake further south. After it passes Riverrun castle, the capital of the Riverlands, the Red Fork passes further to the south and west until it reaches the borders of the Westerlands held by House Lannister.

On the whole, the Riverlands possess few natural defenses or borders. They are bordered to the west and the east by mountains, but these are possessed by the Westerlands and the Vale of Arryn respectively. Rather, these are natural defenses that the Westerlands and Vale possess against the Riverlands. The extensive swamps and narrow isthmus of The Neck also form an effective natural barrier, but these are part of the North under the Starks, again more of a defense against invasion from the Riverlands than the other way around. The southern border of the Riverlands is more or less formed by the upper reaches of the Blackwater River, but this is not a particular impediment to travel between the Riverlands and the Reach to the south. To the southeast, the Riverlands border the Crownlands, but this is purely administrative and not a geographical border. Further, the northwest coast of the Riverlands sits on Ironman's Bay, and is thus open to raiding from the Iron Islands.

All told, the Riverlands border five other regions of the Seven Kingdoms, six if the water border with the Iron Islands is counted (and which due to frequent ironborn coastal raids, it usually is). Thus the Riverlands match the Reach in bordering the largest number of other regions in the Seven Kingdoms. However, the Reach has some natural defenses, such as the Red Mountains along its eastern border, and a large coastline which (while open to ironborn raiding) isn't as open to attack as the long land borders of the Riverlands, which are not very defensible. The Reach is located in the southwest corner of Westeros, while the Riverlands are surrounded on all sides by powerful neighbors. Further, the Riverlands are still fairly close to the Stormlands, to the point that the Stormlands conquered and ruled the Riverlands for 300 years before the Targaryen Conquest (before being pushed out by the Iron Islands).

The Riverlands have a true temperate climate with warm summers and moderately cold winters, which increase in severity north of the Neck. Rainfall is moderate and adequate providing for the fertility of the region.

Castles

 * Riverrun, the former seat of House Tully, the once-ruling house of the Riverlands. Located on the Red Fork of the Trident. The Tullys were attainted following the Red Wedding, and Riverrun and its lands were bestowed upon House Frey.
 * Harrenhal, formerly the seat of House Whent, the largest castle in Westeros, held by some to be cursed.
 * Raventree Hall, the seat of House Blackwood.
 * Seagard, the seat of House Mallister.
 * Stone Hedge, the seat of House Bracken.
 * The Twins, the seat of House Frey.
 * Pinkmaiden
 * Acorn Hall, the seat of House Smallwood

Towns and Settlements

 * Maidenpool, the seat of House Mooton, a port-town near the borders with the Crownlands
 * Stoney Sept
 * Saltpans
 * Pennytree
 * Mummer's Ford
 * Wendish Town
 * Fairmarket
 * The Crossroads Inn

Forests and hills

 * The Hollow Hill, a hideout for the Brotherhood Without Banners
 * High Heart
 * Whispering Wood

Coastal areas

 * The Cape of Eagles
 * Ironman's Bay

Lakes and rivers

 * The Trident
 * Blue Fork
 * Red Fork
 * Green Fork
 * Blackwater Rush
 * Gods Eye
 * Isle of Faces, an island in the Gods Eye

In the books
In the A Song of Ice and Fire novels, the Riverlands is relatively small in size but high in population. It is fertile due to the numerous rivers that run across its expanse, most notably the massive River Trident and its numerous tributaries.

The people of the Riverlands are known as 'rivermen' and are a mixture of hardy warriors, peaceful fisherfolk and devout smallfolk. The Riverlands possess a number of middling-to-large towns, such as Maidenpool, Saltpans, Fairmarket and Stoney Sept.

The borders of the Riverlands are held to be the marshes of the Neck in the far north, the Mountains of the Moon to the north-east, the Blackwater Rush to the south and the hills of the Westerlands to the west.

The Riverlands used to be a kingdom in its own right, but centuries before the Targaryen invasion they were overrun and conquered by the armies of the Storm King. The Storm King couldn't hold such a large territory, especially when the ironborn invaded in force from the west, and was forced to cede the Riverlands to King Hoare of the Iron Islands. The ironborn set about erecting a massive fortress on the lake known as the Gods Eye, completing it on the very day that Aegon the Conqueror set foot on the shores of Westeros. Aegon's dragons burned out the castle, Harrenhal, killing King Harren the Black. Lord Edmyn Tully of Riverrun led a popular rebellion of the river lords against the ironborn, helping Aegon drive them out. For this act, Aegon made House Tully the rulers of the Riverlands in his name.