The Duchy of Rock Coast was a Chisholmian patent of nobility.
Its lands were located in the outmost south-west of the Chisholmian mainland, and included Rock Coast Keep. (map)
The families of Rock Coast and the Duchy of Black Horse were very close, intermarrying over several generations. (BHD)
In the Year of God 896, the reigning Duke of Rock Coast was Zhasyn Seafarer. (MTAT)