If you tuned into "Game of Thrones"killer episode Sunday, you were most likely floored.
What you may not know, is that the graphic episode (read up on the spoilers here) was based on historical events.
Entertainment Weekly caught up with "Game of Thrones" author George R.R. Martin and he revealed the bloody events have roots in Scottish history.
"One was a case called The Black Dinner. The king of Scotland was fighting the Black Douglas clan. He reached out to make peace. He offered the young Earl of Douglas safe passage. He came to Edinburgh Castle and had a great feast. Then at the end of the feast, [the king's men] started pounding on a single drum. They brought out a covered plate and put it in front of the Earl and revealed it was the head of a black boar — the symbol of death. And as soon as he saw it, he knew what it meant. They dragged them out and put them to death in the courtyard. The larger instance was the Glencoe Massacre. Clan MacDonald stayed with the Campbell clan overnight and the laws of hospitality supposedly applied. But the Campbells arose and started butchering every MacDonald they could get their hands on."
The Black Dinner took place in 1440.
Here's a little more on the event from "Our Country, A History of Scotland":
"Douglas and his brother sat at dinner with the king, the chancellor, and the governor. The splendid entertainment was over, and the unsuspecting victims were gaily conversing. Meanwhile, the apartment had been silently beset with armed men who, on a signal from the governor, rushed in and seized the two brothers. The young king wept and clung to the chancellor's knees, vainly begging the lives of his friends. What the earl and his brother said is not on record; but, as the unhappy young men were hurried from the banquet to the block, their countenances, we are told, were "dreary!" Their heads were struck off in the back court of the castle."
38 were killed in the Glencoe Massacre of 1692 after an estimated 120 Campbells woke up early in the morning in the highlands of Scotland.
Again, from "Our Country, A History of Scotland":
"It was four o'clock of a dark winter morning, a storm was raving among the hills, and the wild blasts, laden with snow-drift, swept down the glen. Suddenly the glen rang with musket-shots, and shrieks of fear and agony, and the glare of burning cottages lit up the gloom. The butchery was not nearly so complete as had been intended, by far the greater part of the MacDonald's escaping in the darkness. Thirty-eight of them, however, perished in the atrocious massacre."
SEE ALSO: Why everyone is freaking out over Sunday's "Game of Thrones" episode >
AND: Viewers hysterical reactions to the Red Wedding episode >