House Martell unifies Dorne under their rule as Princes of Dorne
After the defeat of the Rhoynish army by the Valyrian dragonlords in the Second Spice War, Princess Nymeria led the Rhoynar in exile from the Rhoyne aboard ten thousand ships. After years of wandering, the surviving Rhoynar, mostly women, children, and the elderly, landed at the mouth of the Greenblood in southeastern Dorne.
Nymeria made common cause with Mors Martell, Lord of the Sandship, whose lands were dwarfed by those of powerful kings such as House Yronwood. On the day she wed Mors, forming House Nymeros Martell, Nymeria had her fleet burned to affirm that the Rhoynar could not return to Essos. The people of the Martell lands also intermarried with the Rhoynar, and the addition of the Rhoynar increased the strength of the Martells tenfold. Nymeria declared Mors to be the Prince of Dorne, using the Rhoynish title of prince instead of the Westerosi "king". Equal primogeniture was also introduced.
The campaign of Nymeria and Mors to conquer Dorne took years to accomplish, as they had to defeat numerous lords and petty kings in succession. Although the Martells gained the support of the Fowlers, Tolands, Daynes, and Ullers, for nine years Mors battled their last and greatest opponent, King Yorick V Yronwood, whose supporters included the Jordaynes, Wyls, Blackmonts, and Qorgyles. Although Yorick slew Mors in the Third Battle of the Boneway, Nymeria continued the war and eventually forced the Yronwoods into submission after another two years.
By war's end Nymeria had sent six kings to the Wall: Yorick Yrownood, Vorian Dayne, Garrison Fowler, Lucifer Dryland, Benedict Blackmont, and Albin Manwoody. The fortress of Sunspear was made capital of Dorne, and House Martell has ruled ever since. The Rhoynar influence remains strong in Dorne.