How the Templars were founded

In a subliminal message in a video game, Assassins Creed 2, it explains Cain's story.

Cain was a domestic criminal in Great Britain in the 12th century. Cain also was a Satan-worshipper at a time where Satanism was unpopular. He had murdered countless people and was Britain's most notorious serial killer, though much evidence of his existence has been destroyed. In 1131, Cian was visited by Satan humself where upon Satan, he had an ancient powerful artifact, the Holy Grail. Satan told him what he wanted, a world empire under the Antichrist and he wanted him to take the Holy Grail and use it to create world government and ultimately lend the world to Satan. According to religious belief, Cain signed a contract with his own blood and sold his soul. Satan then said unto Cain "You thou shall not speak of this, if you thy you will be choked and suffer tortment eternly". He then was granted the Holy Grail and established the Templar Order and began the agenda.Cain soon murdered his family in the fear they would discover the Holy Grail and there still is a painting of him killing his brother.