Lord of Sunspear

From Asoiaf

Lord of Sunspear is a title traditionally held by the Prince of Dorne. Doran Nymeros Martell is the current Prince of Dorne.

Nymeria, warrior queen of the Rhoyne, landed in Dorne with ten thousand ships and married Mors Martell, Lord of Sunspear. With her help Mors vanquised his rivals to become the first Prince of Dorne.