From A Wiki of Ice and Fire
The Stormlands is one of the constituent regions of the Seven Kingdoms on the continent of Westeros. It was formerly a sovereign nation by the same name until the War of Conquest, in which the last Storm King was slain. The Stormlands are ruled from the castle of Storm's End by House Baratheon. They are so-named for the savage and frequent storms that batter the coast. Bastards born in the Stormlands are given the surname Storm.
- See also: Category:Places in the Stormlands
The Stormlands are bordered to the north by the Crownlands, west by the Reach, south by Dorne and the Sea of Dorne, and east by Shipbreaker Bay and the narrow sea. It is one of the smaller regions of Westeros, a land of harsh mountains, stony shores, and verdant forests, including the kingswood and the rainwood along Cape Wrath. Although it is rainy, the region is fertile enough. The kingsroad runs north from Storm's End to King's Landing in the Crownlands.
The Dornish Marches, located in the south-west in a long salient along the Red Mountains, serve as an effective buffer zone between the Stormlands and their old enemies of the Reach and Dorne. For centuries it was a regular battleground, changing hands more than once until Dorne became part of the Seven Kingdoms.
A few islands, including Tarth and Estermont, are also considered part of the Stormlands. Ships coming across the narrow sea avoid the notorious Shipbreaker Bay and its storms, though the seas along the Stormlands can be clear and blue. The waters around Tarth are particularly famed for their clear blue color, earning Tarth the name "Sapphire Isle."
The Stormlands were the domain of the Storm Kings, whose territory in eastern Westeros once stretched from Cape Wrath to the Bay of Crabs and, after conquering the River Kings, north to the Neck. For thousands of years the Stormlands were also the first line of defense against Dornish incursions from the south, so they have strong martial traditions and a number of strong castles, especially the marcher lords.
However, the power of the Storm Kings declined over centuries due to pressure from the Reach to the west and Dorne to the south. The Storm King Arrec Durrandon then lost the Riverlands to Harwyn Hardhand of the Iron Islands. Arrec's grandson, King Argilac Durrandon, killed King Garse VII Gardener at Summerfield and also fought alongside Pentos and Tyrosh against Volantis during the Century of Blood.
Argilac the Arrogant was the last Storm King, however, as he was slain in the Last Storm during Aegon Targaryen's War of Conquest. Argilac's lands, titles, sigil, and house words were given to Orys of House Baratheon, who married Argilac's daughter, Argella Durrandon. Under Targaryen rule, the Baratheon storm lords continued to battle the Dornishmen until their incorporation into the Seven Kingdoms by King Daeron II Targaryen.
Robert's Rebellion saw the Baratheons raise a rebel alliance against Targaryen rule. When Lord Robert Baratheon returned from the Vale of Arryn to call his banners, he first had to defeat his recalcitrant bannermen at Summerhall before marching north to his eventual victory at the Trident. Robert's middle brother, Stannis, defended Storm's End during a siege by Lord Mace Tyrell of the Reach. Robert claimed the Iron Throne, forming the royal House Baratheon of King's Landing. Stannis took and was given Dragonstone, while the youngest brother, Renly, succeeded Robert as Lord of Storm's End.
A Game of Thrones
King Robert Baratheon dies after hunting boar in the kingswood. Rather than kneel to the new king, Robert's alleged son Joffrey Baratheon, Renly Baratheon, Lord of Storm's End, escapes King's Landing and allies with the Tyrells of Highgarden.
A Clash of Kings
During the War of the Five Kings, the storm lords almost unanimously support Robert's youngest brother, Renly, before switching allegiance to the middle brother, Stannis, after Renly's death at Storm's End.
A Storm of Swords
Most of Stannis's bannermen kneel to King Joffrey Baratheon after Stannis's defeat in the Battle of the Blackwater. Aside from garrisons at Storm's End and Dragonstone, the remaining lords loyal to Stannis travel with him to defend the Wall and Castle Black from wildlings. King Joffrey dies at his wedding, and he is succeeded by his younger brother, Tommen Baratheon.
A Feast for Crows
Lords Mace Tyrell and Mathis Rowan lay siege to Stannis's garrison at Storm's End. Mace returns to King's Landing when he hears that his daughter, Queen Margaery Tyrell, has been arrested, leaving Mathis to continue the siege.
A Dance with Dragons
Aside from Stannis's garrison at Storm's End, the Stormlands hold to the peace of King Tommen. Led by Jon Connington and Aegon Targaryen, however, the Golden Company invades Estermont and Cape Wrath, quickly taking Griffin's Roost, Greenstone, Rain House, and Crow's Nest.
House Baratheon of Storm's End.
House Buckler of Bronzegate.
House Cafferen of Fawnton.
House Caron of Nightsong.
House Connington of Griffin's Roost.
House Dondarrion of Blackhaven.
House Errol of Haystack Hall.
House Estermont of Greenstone.
House Fell of Felwood.
House Grandison of Grandview.
House Mertyns of Mistwood.
House Morrigen of Crow's Nest.
House Peasebury of Poddingfield.
House Penrose of Parchments.
House Rogers of Amberly.
House Selmy of Harvest Hall.
House Staedmon of Broad Arch.
House Swann of Stonehelm.
House Tarth of Evenfall Hall.
House Trant of Gallowsgrey.
House Wylde of Rain House.