Baron of Roslin was a Scottish feudal barony held by the chief of the Clan Sinclair.
No certain record exists but it is likely that the Sinclairs came from Saint-Clair-sur-Epte in Normandy. William of Saint-Claire accompanied Saint Margaret of Scotland, daughter of Edward the Exile to Scotland in 1068, where she eventually married Malcolm III of Scotland. In return for his efforts, the king supposedly granted Sinclair the barony of Roslin "in free heritage".Roslin Castle was built beginning about 1390, under Henry I Sinclair, Earl of Orkney. Roslin castle was destroyed in 1544, rebuilt in the late 16th century, but again destroyed and abandoned in 1688.
Barons of Roslin are on record for the 13th to 14th century:
In 1379, Henry Sinclair, Baron of Roslin (c. 1345 - c. 1400) was created Earl of Orkney. From this time, the Roslin barony became just one of a larger set of possessions held by the earls (from 1455 Earls of Caithness instead of Orkney).
The Roslin barony was abandoned in the 16th century with the destruction of Roslin Castle; the estate was now held by junior members of the Sinclair family