| William St Clair | |
| Baron of Roslin | |
| Predecessor: | John St Clair, 17th Baron of Roslin |
| Successor: | Alexander St Clair, 19th Baron of Roslin |
| Noble Family: | Clan Sinclair |
| Father: | William St Clair, 16th Baron of Roslin |
| Mother: | Dame Anna Spotswood |
James St Clair was a Scottish nobleman and the 18th Baron of Roslin.
He was the third son of William St Clair, 16th Baron of Roslin and Dame Anna Spotswood, daughter of John Spottiswoode who was the Archbishop of Glasgow and later the Archbishop of St Andrews and Chancellor of Scotland. His elder brother was John St Clair, 17th Baron of Roslin who died in 1690 and whom he succeeded.[1]
He redeemed the estate of Roslin and was an apprentice in London after which he went to France where he spent time with Mr Monteith who was the author of The Troubles of Great Britain, then settled with the Knight of Malta, Great Prieur of France. He later entered into service with the Archbishop of Corinth to who he dedicated his book Troubles of Brittany. He later served Lord Rutherford the Viscount Teviot as his secretary in Dunkirk and at Tangier in Africa. He was later Commissar of Shetland.[1] [2]
He did not re-build Roslin Castle after it had been destroyed by Oliver Cromwell's troops under General Monk during the time of his elder brother, John St Clair, 17th Baron of Roslin.[3]
James St Clair, 18th Baron of Roslin married to Jean, daughter of Henry Spotswood the Sheriff of Dublin. They had the following children:[1]