Advocate and judge. Born into a legal family, the son of James Ferguson of Badifurrow , who bought the estate of Pitfour near Mintlaw in Aberdeenshire in 1700. Ferguson was a successful lawyer, who served as Dean of the Faculty of Advocates in Edinburgh until 1764 when he was raised to the bench as Lord Pitfour. James Boswell described Ferguson as "the greatest lawyer in Scotland and one of the best of men, possessed of good sense, honesty, and meekness". He was also responsible for laying out model villages near his home including New Deer, Longside and Mintlaw.
Ferguson was also able to enlarge the estate of Pitfour and restore the family fortunes, which were seriously depleted by the South Sea Bubble. In 1733, he married Anne Murray (1708-93), daughter of Lord Elibank. One of their sons, Patrick, invented the breech-loading rifle but was killed South Carolina during the American Wars of Independence.
