He was the only surviving son of John Scollay, a strong supporter of colonial rights and a member of Boston's Board of Selectmen in 1764.
William was extremely active in the community and was named a Colonel in the Boston Regiment.
Eventually the name changed to Scollay's Square and was officially recognised by Boston in 1838.
William Scollay's sister, Priscilla married Colonel Thomas Melvill, a participant in the Boston Tea Party.
Scollay was the Deputy Grand Master of the Freemasons of Massachusetts in 1795 when a box containing an assemblage of commemorative items was deposited under the corner of the Massachusetts State House on 4 July 1795 by Governor Samuel Adams, assisted by the Grand Master, Paul Revere, and Deputy Grand Master.