There were many witch trials going on in Scotland, especially in the 17th century. Somewhere between 3,000 and 4,000 accused witches may have been executed in Scotland in during the period of 1560-1707. Around 2,000 of those witches were killed in the 60 years from 1620-1680. The first round of persecution occurred 30 years earlier in 1590 in North Berwick (witches.net).
This round of trials lasted two years in which 70 people were accused including Francis Stewart, 5th Earl of Bothwell on charges of high treason. After arrested, most of the “witches” were tortured and then the majority of them confessed. The key piece of information that was tortured out of these people was that they held their covens on the Auld Kirk Green, part of the modern-day North Berwick Harbor area (Ankarloo).
As absurd as it sounds, these trials were actually started by the royals who were blaming “witches” for a horrible storm they got stuck in. The way the story goes King James VI sailed to Copenhagen to marry Princess Anne, sister of Christian IV, King of Denmark. On their way back to Scotland they got caught in terrible storms and had to shelter in Norway for several weeks before continuing. The admiral of the Danish fleet that was escorting the couple blamed the storm on the wife of a high official in Copenhagen whom he had insulted before. This then caused several nobles of the Scottish court to be implicated, and witchcraft trials were held in both countries (Ankarloo).
After that whole ordeal over a hundred suspected witches in North Berwick were arrested. During the torture I had mentioned earlier, many confessed to having met with the Devil in the church at night, and devoted themselves to doing evil. These evil things they did included poisoning the King and other members of his household, and attempting to sink the King's ship (Ankarloo).
The most famous story perhaps of this trial was of Agnes Sampson who was examined by James VI at his palace called Holyrood House. She was fastened to the wall of her cell by a witch's bridle. A witch’s bridle was an iron instrument that had 4 sharp prongs that were forced into the mouth, so that two prongs pressed against the tongue, and the two others against the cheeks. She was kept constantly awake by a rope that was placed around her neck so that if she nodded off she would end up strangling herself. It was only after these torturous ordeals did Agnes Sampson confess to the fifty-three indictments against her. She was then finally executed by being strangled and then burned (Ankarloo).
Ankarloo, B., Clark, S. & Monter, E. W. () Witchcraft and Magic in Europe.
Image is artist's rendering of the North Berwick Trials, courtesy of Itscotland.org.uk