William St Clair of Roslin, 20th Laird and feudal Baron of Roslin (1700-1778) was the first Grand Master Mason of the Grand Lodge of Scotland. He became the first Grand Master Mason by acclamation on St. Andrew’s Day in 1736. He was initiated in Lodge Canongate Kilwinning on 18 May, Passed on 2 June 1736 and Raised on 3 November 1736. He was supposedly the last of a long line of hereditary Grand Masters and surrendered his hereditary office on becoming the first elected Grand Master of the new Grand Lodge of Scotland. However his ancestors were actually only asked to become “Patrons and protectors” of the Scottish Stone Masons, according to the ‘Sinclair Charters’ and never “Hereditary Grand Master Masons” as the foundational myth of the Grand Lodge of Scotland suggests. 

• Barony of Roslin – Wikipedia (list of the Lairds of Roslin)
• William Sinclair, 1st Earl of Caithness – Wikipedia (founder of Rosslyn Chapel)
• William St Clair of Roslin – Wikipedia (1st Grand Master of the Grand Lodge of Scotland)
• Earl of Rosslyn – Wikipedia