William St Clair | |
|---|---|
| Baron of Roslin | |
 Baron of Roslin coat of arms | |
| 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.