The eighteenth century abounds with colourful, eccentric figures, some famous and others known by but few readers. Sir John Dalrymple of Cranston, was such a person, curious in his interests and controversial in his activities even for his time. Historians of modern Roman Catholicism have long recognized that he played a part in the negotiations which led to the English Roman Catholic Relief Act of 1778, but they have mentioned him only in passing. Their sketchy references to his role usually derive in one way or another from Fr. James Stother’s account of the abortive negotiations for Scottish relief, which paralleled the more successful discussions on behalf of English and Irish Catholics. Stother’s chronicle, published over a century ago, remains by far the most extensive account of Sir John’s activities in print, although it is itself brief and discreet. Advancing projects for Catholic relief required caution at the very least, and the project for the Scots, beyond this, demanded secrecy, in so far as relief in the northern kingdom involved concessions to Catholics in return for their encouragement of troop enlistment in the controversial American war. Concealment by Sir John and his associates of the role he played at the time has led to neglect of that role by historians ever since.