Impalement
Given his name, it should come as no surprise that this was the most favored method of execution by Vlad the Impaler. In 15th century Romania; the victim was forced to sit on a sharp and thick pole. When the pole was then raised upright, the victim was left to slide down the pole with their own weight. It could take the victim 3 days to die using this method and it has been said that Vlad once did this to 20,000 people all while enjoying a meal.
