The Stormlands are situated in a position quite central to the game, and border many other factions. When the player starts the game, he starts in the Stormlands. On the default map, you can recognize the Stormlands by it's yellow colour.
Capital is Storm's End.
The Stormlands traditionally was the homeland of the Stormkings. After the Targaryen conquest, the Baratheon dynasty became the Lords Paramount of the region, seated in the famous castle Storm's End. During the reign of Mad King Aerys, Lord Steffon Baratheon and his wife died in a tragic accident. Their heir was the eldest of their three sons, the teenager Robert Baratheon.
Later, when Robert rose against the Mad King, the castle Storm's End was held by the middle Baratheon son, King Stannis Baratheon. When Robert's Rebellion succeeded, House Baratheon became the royal house. When Robert died, both his younger brothers rose against his heirs, whom they believed to be illegitimate. However, instead of rising together, they both pressed their seperate claims. King Stannis Baratheon rose, together with local lords and religious converts, from his seat in Dragonstone. Most of the stormlords however, chose to follow the younger Baratheon brother, Renly, who, though lacking the judical claim, pressed for kingship on grounds of his far larger popularity and his alliance with the Tyrells, who controll the Reach.