Dorne is the southernmost and least populated land of Westeros. The capital, Sunspear, is the seat of the ruling House Martell. As of the first four books, Doran Nymeros Martell is the Prince of Dorne and Lord of Sunspear. Doran's sister, Princess Elia, was married in a political alliance to Prince Rhaegar Targaryen, the Prince of Dragonstone and heir to the Iron Throne. They had two children, a daughter, Rhaenys and a son, Aegon. During the War of the Usurper Princess Elia was captured and raped by Gregor Clegane, a House Lannister bannerman (vassal). She and her children were murdered. Prince Doran and his wife, Princess Mellaria, have three children, Arianne, Quentyn and Trystane. During the War of the Five Kings, Tyrion Lannister, as Hand of the King, turns the historical enmity of House Martell and Dorne into an alliance by sending King Joffrey's middle sibling and sister, Myrcella Baratheon, as the betrothed future bride to Trystane, the youngest child of Prince Doran, who is about her own age. The eldest child of Prince Doran, Arianne, is heir to House Martell, Sunspear and the rule of Dorne. The wealth of Dorne comes from their famous Sand Steeds, purebred horses of endurance, speed and grace, and from with spices, wines, fishing, fabrics and textiles.
Dorne is bordered by the Sea of Dorne to the north, the islands known as the Stepstones to the east, and stretches from the high mountains of the Dornish marches, the Red Mountains, separating Dorne from the remainder of the Seven Kingdoms by land. The two major passes though the Red Mountains that connect Dorne with the rest of the continent are the Stone Way Pass and the Prince's Pass. The Prince’s Pass leads to the Reach, while the Stone Way exits the mountains near Summerhall. The southern coast of the continent is bordered by the Summer Sea. It is the hottest kingdom in Westeros and the region is rocky, mountainous, arid and dry, featuring the only desert on the continent. Its rivers provide some fertile lands and even during a long summer there is enough rain and other supplies of water to keep Dorne habitable. Inland water is almost as valuable as gold, and wells are jealously guarded. Notable locations of Dorne are Starfall, the seat of House Dayne, and Yronwood, the seat of House Yronwood, the most powerful of the Martell bannermen. Planky Town is a trade port town at the mouth of the River Greenblood.
Dornishmen have a reputation for hot-bloodedness. They differ both culturally and ethnically from other Westerosi due to the historical mass immigration of Rhoynish people. They have adopted many Rhoynish customs as well, including equal primogeniture. Dorne was the only kingdom in Westeros to successfully resist Aegon's conquest. It joined the Seven Kingdoms through marriage over a century after the Targaryen invasion. This accomplishment has allowed Dorne to retain a measure of independence. Lords of the ruling House Martell still style themselves "Prince" and "Princess" in the Rhoynish fashion. Unlike most of the rest of Westeros, illegitimate children born in Dorne are treated nearly the same as legal offspring and given the surname Sand, as with Westerosi customs to give bastards a surname showing their origins.
Martin said "You don't get the real tropical stuff til you get down south to Dorne."
According to A Storm of Swords, "There were three sorts of Dornishmen . There were the salty Dornishmen who lived along the coasts, the sandy Dornishmen of the deserts and long river valleys, and the stony Dornishmen who made their fastnesses in the passes and heights of the Red Mountains. The salty Dornishmen had the most Rhoynish blood, the stony Dornishmen the least. All three sorts seemed well represented in Doran’s retinue. The salty Dornishmen were lithe and dark, with smooth olive skin and long black hair streaming in the wind. The sandy Dornishmen were even darker, their faces burned brown by the hot Dornish sun. They wound long bright scarfs around their helms to ward off sunstroke. The stony Dornishmen were biggest and fairest, sons of the Andals and the First Men, brownhaired or blond, with faces that freckled or burned in the sun instead of browning."
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