Dorne

Dorne occupies the southern tip of Westeros. The Sea of Dorne runs along one side, the Stepstones sit off another, and the Summer Sea closes off the rest of the coastline. Inland, a mountain range — the Dornish Marches — blocks the way, with only two gaps crossing it: the Prince's Pass toward the Reach and the Boneway toward the Stormlands. Sunspear, its capital, lies on the far side of those peaks.

No other corner of Westeros runs as hot or as dry: rock, drought, and rain scarce even in summer. What keeps the interior livable are its rivers, and inland a well or spring gets guarded like gold. Between the size of the land and the climate, Dorne ends up the least populated of the Seven Kingdoms.

A thousand years before this story, Dorne was a patchwork of small, poor Andal statelets, none of them strong enough to rule over the rest. That changed when the Rhoynar arrived, led by their warrior queen Nymeria, who allied herself with Mors Martell, lord of Sunspear. Between the two of them they subdued the whole peninsula and left it united under one throne, that of House Nymeros Martell.

Much of what sets Dornishmen apart from the rest of Westeros comes from that moment. Their rulers are styled prince and princess rather than lord and lady, and Rhoynar customs carry more weight than Andal ones. Along the Greenblood, some descendants of the Rhoynar still worship the Mother Rhoyne, though the Faith of the Seven remains the common religion elsewhere in the realm. A bastard born in Dorne takes the surname Sand. With the Marcher houses, the relationship was one of violence for centuries, and the border with the Reach is still disputed.

Roughly six thousand years after the Rhoynar arrived, Aegon the Conqueror landed in Westeros and set off the War of Conquest, putting down the Andal kings one by one. The Dornishmen never gave him the open battle other kingdoms did.

Instead they struck in quick ambushes and raids, then vanished into the desert and the mountain passes, where not even dragons could find them. Over the years, Aegon simply let Dorne be.

A century and a half later, King Daeron I managed to conquer Dorne. Rebellion broke out almost at once, and the war ended with Daeron dead along with forty thousand soldiers. Dorne won its independence back. Years later, Daeron's successor, Baelor the Blessed, made peace with the Dornish.

The lasting union came a different way: King Daeron II married Princess Myriah Martell, while his younger sister, Princess Daenerys, married the Prince of Dorne, Maron Martell. Through those two marriages, Dorne joined the Seven Kingdoms by alliance rather than conquest. Even so, the realm kept a streak of independence that had faded elsewhere in Westeros.

During the War of the Usurper, no battles were fought inside Dorne itself, only a few skirmishes along the border. Crown Prince Rhaegar Targaryen was married to Princess Elia Martell, and she was killed in the sack of King's Landing along with her children.

Afterward, House Martell kept a cold relationship with Robert Baratheon and stayed out of life at court.