Warden of the Sands
From A Wiki of Ice and Fire
When King Aegon I Targaryen left Dorne to return to King's Landing, he named Lord Jon Rosby the Castellan of Sunspear and the Warden of the Sands. The Dornishmen soon rebelled, however, and Rosby was killed in the Defenestration of Sunspear.
- The World of Ice & Fire, Dorne: Dorne Against the Dragons.