Imagine if by chance, a Lightsaber was transferred using a time machine to the middle ages.
At first it was found by a peasant. The poor fellow didn't know what to do with it, so he sold it for a few coins to an artifact collector who was obsessed by cleaning and shining his artifacts. After three years, one time while the collector was busy shining the Lightsaber he accidentally activated it while pointing it to his heart; he died immediately.
The son of the collector found the Lightsaber next to his father's corpse and immediately knew that the artifact was diabolic, so he ran to the town's priest and told him about his discovery. The priest had equipped himself with some religious tools (a bible, a cross and some holy water) and went along with the son to the collector 's house. Scared from the laser coming out of the artifact, he told the son that this was indeed the devil's work, but in order to maintain his credibility he had to do something holy about it, so he put the cross on top of the Lightsaber and accidentally deactivated it.
Now, the priest suggested to purify this artifact with fire (bad idea), so the next day, he gathered the people in the town's center where he prepared a huge fire. He grabbed the Lightsaber with his hand and while walking towards the fire he tripped, and while falling he accidentally activated the Lightsaber and killed himself. Shocked by this unholy scene, the town's people ran away screaming, except for one clever fellow who happened to be an engineer.
Out of curiosity he wanted to investigate this artifact, so he grabbed the Lightsaber and inspected it carefully,. After hours of deep inspection, he concluded that this artifact was nothing but a sword of some kind he never saw before. Then he decided to test its might and was amazed by the power of this thing, so he decided to give it as a gift to the King for a position in the king's court. The king called his Lightsaber 'The Sword of Power', claiming that God wanted him to have it because he is the true king that shall rule this Earth, and so ballads have spread across the Earth praising the Sword of Power and his king, and the eyes of everyone have turned towards this kingdom, which brings me to my question :
What implications will this Lightsaber have during the Middle Ages on :
1 - Society.
2 - Warfare.
3 - Technology.