William St Clair, 16th Baron of Roslin
William St Clair (died 1650) was a Scottish nobleman and the 16th Baron of Roslin. Early life. He was the son of William St Clair, 15th Baron of Roslin and his wife Jean or Janet Edmondstone, daughter of the Laird Of that Ilk. He succeeded to the estates of Roslin upon the death of his father in 1610. Baron of Roslin. William St Clair, 16th Baron of Roslin received a charter of the Hereditary Protectorate from the Scottish Freemasons in 1630. He objected to the appointment of Anthonie Alexander to be the Master  of Work to the Crown of Scotland as being in prejudice to his hereditary charge of the Masons of the Kingdom. He added to his family's ancestral halls at Roslin Castle and built a structure over the vaults. He was a loyalist and supported the cause of Charles I of England. Death. He died during the Civil War and was interred in Rosslyn Chapel on the same day that the Battle of Dunbar was fought on September 3, 1650. Family. Wiliam St Clair, 16th Baron of Roslin married, in 1609, to Dame Anna Spotswood, daughter of John Spottiswoode who  was then the Archbishop of Glasgow and later the Archbishop of St Andrews and Chancellor of Scotland. They had the following children: