Vlad the Impaler was not a mass murderer. He defied the Sultan of the Ottoman Empire at a time when this empire was the greatest power in the world (15th century). Ottoman rulers were notorious for their cruelty (although it is also recognized that their cruelty was paralleled by that of his Western counterparts).
Vlad the Impaler was constantly at war with the Ottoman Empire, which was actively conquering the Balkans at that time. In times of battle, he fought on the front line together with his troops. And he respected his subjects. He did use murder and terror in ruling the tiny kingdom he had managed to inherit. But the only people he terrorized were the Ottomans and the noblemen that plotted against him.
Vlad the Impaler’s father was Vlad II, who had been killed by local noblemen. Vlad the Impaler was Vlad III. Vlad III’s brother, Mircea II, who ruled before him, was also killed by local noblemen. One of the noblemen who participated in these killings was Vladislav II, who occupied the throne until Vlad III killed him in hand-to-hand combat.
It is naive to mistake Vlad the Impaler for the fictitious character that the public seems to cherish. Really, to regard Vlad III’s rule as a benchmark cruelty is to ignore not only his actual reign but also the context of the Medieval Era in which he ruled: “The final authority in this era was force, and the general atmosphere of the time was one of violence. Defiant vassals frequently made war upon their lords. But warfare was also considered the normal occupation of the nobility, for success offered glory and rich rewards.” (http://history-world.org/Mid%20political_organization.htm)
As for his actual reign, here is what wikipedia has to say in the introductory paragraph of the article on Vlad III (the Impaler):
[ul]
[li]He was a three-time Voivode of Wallachia, ruling mainly from 1456 to 1462, the period of the incipient Ottoman conquest of the Balkans.[/li]
[li] His father, Vlad II Dracul, was a member of the Order of the Dragon, which was founded to protect Christianity in Eastern Europe. [/li]
[li]Vlad III is revered as a folk hero in Romania and Bulgaria for his protection of the Romanians and Bulgarians both north and south of the Danube.[/li]
[li]Following his raids on the Ottomans, a significant number of Bulgarian common folk and remaining boyars resettled north of the Danube to Wallachia and recognized his leadership.[/li][/ul]
Vlad III (the Impaler) lived about 500 years before Leopold II. He may have been a ruthless Medieval ruler, but he was not an assassin.
What Leopold II did to the Congolese is similar with what the Turkish did to the Armenians, and both genocides occurred in the early 20th century. Leopold was familiar with the notions of Rights of Man, promoted by the French and American Revolutions. The fact that he chose to ignore them and to kill millions of people for his own financial benefit makes him a despicable leader. An assassin.